Bugzilla Bug 186365

After upgrading from alsa-lib-1.0.14_rc3 to alsa-lib-1.0.14a(-r1), all sound
apps stop working. Errors vary, but on command line play this is what I get.

ALSA lib dlmisc.c:118:(snd_dlsym_verify) unable to verify version for symbol
_snd_pcm_empty_open
ALSA lib pcm.c:2108:(snd_pcm_open_conf) symbol _snd_pcm_empty_open is not
defined inside (null)
play stio: Failed writing default: cannot open audio device

Other apps report no alsa device or etc. Reverting back to previous alsa-lib
versions makes all apps work again immediately after emerge. Not sure if apps
need to be re-compiled against the newer alsa-lib, newer kernel, or what.

Happy to provide additional info or etc upon request. Just let me know what you
need from me if anything to assist in coming up with a resolution. Thanks

Created an attachment (id=125772) [edit]
emerge --info

Well, then don't use USE="-*" next time ;)

*** This bug has been marked as a duplicate of bug 183451 ***

(In reply to comment #2)
> Well, then don't use USE="-*" next time ;)

FYI, I was told to by someone who was involved with adding those use flags.
Thus the combo I have set I got from them. Not anything I came up with on my
own or etc. Can't find log of chat, if it was logged, so not sure exactly who I
got this from.

Ok this is not a dub so re-posting comments from other bug here.

Re-opening bug for resolution :)

Ok, it looks as if these plugins are no longer optional. IMHO they should not
be optional anymore, flags removed etc.

asym dmix empty softvol

Before alsa-lib-1.0.14a this worked
ALSA_PCM_PLUGINS="iec958 ioplug plug"

Now I have to have set
ALSA_PCM_PLUGINS="asym dmix empty iec958 ioplug plug softvol"

Even though alsa-lib builds without those plugin flags set. Till we have a use
case where it works less those flags. They should be dropped as flags, and
plugins included all the time. Or by default at min, prefixing flags with a no.

FYI, I determined those flags are required via trial and error. Starting with
using the play command to play a mp3. Which produced the following.

ALSA lib dlmisc.c:118:(snd_dlsym_verify) unable to verify version for symbol
_snd_pcm_empty_open
ALSA lib pcm.c:2108:(snd_pcm_open_conf) symbol _snd_pcm_empty_open is not
defined inside (null)
play stio: Failed writing default: cannot open audio device

Noticing empty in the above I added that flag. Then when I issued play again I
god different errors. The ones listed below are the symbols from those errors.
Error was basically same as above.

_snd_pcm_asym_open
_snd_pcm_softvol_open
_snd_pcm_dmix_open

So one by one as I added a flag and play produced a different error. I looked
at the name in the symbol, found the corresponding flag, added it. And now I am
hole again and all my machines have a working ALSA again :)

Why are use setting the variable ALSA_PCM_PLUGINS anyway (I guess in
/etc/make.conf, right?)?
If you don't set it, you get all the plugins and no errors.

Greetings, Andreas.

(In reply to comment #6)
> Why are use setting the variable ALSA_PCM_PLUGINS anyway

Answered in comment #3

(In reply to comment #7)
> > Why are use setting the variable ALSA_PCM_PLUGINS anyway
> 
> Answered in comment #3

Okay, somebody told you to do that.
Did you try without yet?
Why did you have to set USE="-*" and ALSA_PCM_PLUGINS in the first place?

Bye, Andreas.

(In reply to comment #8)
> 
> Okay, somebody told you to do that.

Yes, pretty sure the person/developer who added the flags in the first place. I
got it from #gentoo-dev, which is pretty much a dev only voice channel.

> Did you try without yet?

If you see comment #4, I did trial and errors to find which ones were needed,
beyond the ones I have used for months now.

> Why did you have to set USE="-*" and ALSA_PCM_PLUGINS in the first place?

I never set "-*", I never stated I set that. It's not in my emerge --info
attached. It's an incorrect assumption that was made in comment #2. When tying
this bug to another with that issue. But it's unrelated, and not the same at
all.

OK, I just finally fixed it in the tree. All issues related to this should now
be gone, as the alsa-lib ebuild now forces a bare minimum of plugins which need
to be (as William pointed out in #c4).