Re: [fluid-dev] Re: An evil screeching noise when playing

[Josh Green]

On Sat, 2005-10-15 at 12:24 +0300, Kimmo Sundqvist wrote:
> On Saturday 15 October 2005 11:51, Kimmo Sundqvist wrote:
> 
> > As soon as I have time, I will narrow the problem down to one USE variable.
> >  I remember doing this before, but couldn't remove the screech no matter
> > what I disabled.  I don't know what has changed since then.
> 
> The problem appears and disappears depending on the use of SSE.  I found this 
> inside the script (ebuild) that Portage uses to build Fluidsynth.
> 
> /usr/portage/media-sound/fluidsynth/fluidsynth-1.0.6.ebuild in any recent 
> machine running Gentoo linux has the following lines:
> 
>         if use sse; then
>                 myconf="--enable-SSE ${myconf}"
>                 # If your CFLAGS include optimizations for sse, ie:
>                 # -march=pentium4 -mfpmath=sse -msse2
>                 # AND your USE flags include sse, ie: USE=sse,
>                 # the sounds with fluidsynth will be distorted.
>                 if [ `is-flag "-march=pentium4"` ]; then
>                         filter-flags "-msse2"
>                         filter-flags "-mfpmath=sse"
>                 fi
>         fi
> 
> I feel silly that I didn't examine the ebuild carefully enough until now.
> 
> My CFLAGS are "-Os -mcpu=pentium3 -pipe" and I don't know why mcpu=pentium3 
> is 
> not excluded in the ebuild, why mcpu includes SSE optimizations (since it is 
> not march=pentium3 which could and should include them) and why GCC's SSE 
> optimizations conflict with Fluidsynth's.
> 
> What can you tell me about this?
> 
> -Kimmo S.
> 

The ebuild should not be using SSE.  I think I'm going to go ahead and
change the --enable-SSE option in FluidSynth to
"--enable-experimental-SSE" or something and make the "--enable-SSE"
option display a nice warning that SSE isn't actually being used.  I
think a lot of distributions have likely been using this option since
there wasn't any mention of it being an experimental feature.  I'm not
really sure in what state the LADSPA support is in either, there could
be issues with that as well.  Thanks for reporting these issues, since
they should be dealt with properly :)  Best regards,
        Josh Green

signature.asc
Description: This is a digitally signed message part