[FFmpeg-devel] [PATCH] H264 DXVA2 implementation

Uoti Urpala uoti.urpala
Sun Jan 10 17:39:30 CET 2010

On Sun, 2010-01-10 at 16:54 +0100, Reimar D?ffinger wrote:
> On Sun, Jan 10, 2010 at 01:45:17PM -0200, Ramiro Polla wrote:
> > On Sun, Jan 10, 2010 at 1:22 PM, Reimar D?ffinger
> > <Reimar.Doeffinger at gmx.de> wrote:
> > > And to say something constructive: I suggest adding check for a define that if set
> > > will remove the non-portable bitfields and (if any remain) name the remaining unions/structs
> > 
> > Or we could set -fms-extensions for that file, see
> > http://gcc.gnu.org/onlinedocs/gcc/C-Dialect-Options.html
> Which of course means the requirements for FFmpeg change from "requires a C99 compatible compiler" to
> "requires a compiler compatible to some bastardized mix of C99 and whatever Microsoft calls C", not to
> mention that you'd probably also need -mms-bitfields.

Anonymous unions by themselves are not Microsoft-specific; they're part
of standard C++, enabled by default in gcc (only the pedantic -std=c99
disables them), and used in the Linux kernel for example.
"-fms-extensions" enables more Microsoft-specific extensions. I don't
know whether there is any separate option to allow just normal anonymous
unions (more specific than using -std=gnu99 instead of -std=c99).

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