Hi all,


bugs like [1] makes clear to me that the increasing number of CPU
extensions USE flags is getting more and more confusing.

ffmpeg-0.6_p25767.ebuild : IUSE="+3dnow +3dnowext alsa altivec amr
bindist +bzip2 cpudetection custom-cflags debug dirac doc +encode faac
frei0r gsm +hardcoded-tables ieee1394 jack jpeg2k +mmx +mmxext mp3
network oss pic qt-faststart rtmp schroedinger sdl speex +ssse3
static-libs test theora threads v4l v4l2 vaapi vdpau vorbis vpx X x264
xvid +zlib video_cards_nvidia"

(I am not going to argue here that USE defaults shouldn't be used for
CPU extensions.)

Among all CPU extensions USE flags you'll find:

3dnow
3dnowext
mmx
mmxext
sse
sse2
sse3
sse4
sse4a
sse5
ssse3

I probably missed a few, there.

I think it would look a lot less confusing if, using the example above,
the output of emerge would not look like this:

[ebuild N ] media-video/ffmpeg-0.6_p25767 USE="3dnow 3dnowext
bzip2 encode hardcoded-tables mmx mmxext ssse3 zlib -X -alsa (-altivec)
-amr -bindist -cpudetection -custom-cflags -debug -dirac -doc -faac
-frei0r -gsm -ieee1394 -jack -jpeg2k -mp3 -network -oss -pic
-qt-faststart -rtmp -schroedinger -sdl -speex -static-libs -test
-theora -threads -v4l -v4l2 -vaapi -vdpau -vorbis -vpx -x264 -xvid"
VIDEO_CARDS="-nvidia" 0 kB

but more like this:

[ebuild N ] media-video/ffmpeg-0.6_p25767 USE="bzip2 encode
hardcoded-tables zlib -X -alsa (-altivec) -amr -bindist -cpudetection
-custom-cflags -debug -dirac -doc -faac -frei0r -gsm -ieee1394 -jack
-jpeg2k -mp3 -network -oss -pic -qt-faststart -rtmp -schroedinger -sdl
-speex -static-libs -test -theora -threads -v4l -v4l2 -vaapi -vdpau
-vorbis -vpx -x264 -xvid" VIDEO_CARDS="-nvidia" CPU_EXTS="3dnow
3dnowext mmx mmxext ssse3" 0 kB


jer


[1] https://bugs.gentoo.org/show_bug.cgi?id=340539
"media-video/ffmpeg-0.6_p25423 - libswscale/swscale.c:1269: error:
implicit declaration of function 'sws_init_swScale_*'"

On 12/11/10 18:57, Jeroen Roovers wrote:
> Hi all,
>
>
> bugs like [1] makes clear to me that the increasing number of CPU
> extensions USE flags is getting more and more confusing.
>
[snip]

>
> Among all CPU extensions USE flags you'll find:
>
> 3dnow
> 3dnowext
> mmx
> mmxext
> sse
> sse2
> sse3
> sse4
> sse4a
> sse5
> ssse3
>
> I probably missed a few, there.
>

How many packages are affected by those?
I like the idea, but I think changing it around for 2 packages might be
a bit silly. If there's a reasonable amount of packages involved I'm all
for it.

Patrick