This is on a Ubuntu 12.04.1 (fully upgraded) system, but given the nature of the bug it might affect other Ubuntu releases which received a similar upgrade. I first noticed this with MIDI playback which has stopped working in Frescobaldi since a few days because Python can't load its portmidi module. The message I get boils down to the following error from the dynamic linker:
/usr/lib/libportmidi.so.0: undefined symbol: snd_seq_event_input_pending
Downgrading to the previous 1:200-0ubuntu1 version of the package solves the problem. Quite obviously the root cause is a miscompiled libportmidi. Here's what ldd says about the libportmidi.so.0 from the 1:200-0ubuntu1.12.04.1 package:
linux-vdso.so.1 => (0x00007fff9e3ff000)
libporttime.so.0 => /usr/lib/libporttime.so.0 (0x00007fb84ac71000)
libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007fb84a8b2000)
libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007fb84a694000)
/lib64/ld-linux-x86-64.so.2 (0x00007fb84b0af000)
Compare this to the ldd output for the 1:200-0ubuntu1 version:
linux-vdso.so.1 => (0x00007fffe9bff000)
libasound.so.2 => /usr/lib/x86_64-linux-gnu/libasound.so.2 (0x00007f26264cb000)
libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f26262ae000)
libporttime.so.0 => /usr/lib/libporttime.so.0 (0x00007f26260ab000)
libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f2625cec000)
libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f26259f0000)
libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f26257eb000)
librt.so.1 => /lib/x86_64-linux-gnu/librt.so.1 (0x00007f26255e3000)
/lib64/ld-linux-x86-64.so.2 (0x00007f26269f4000)
I haven't checked the sources, but it looks like some linker flags may have gone missing in the 1:200-0ubuntu1.12.04.1 package. So any portmidi application which doesn't happen to link to libasound2 by itself is going to be hosed in a similar way.
Just for the record, here's the full traceback from Frescobaldi (but note that the last line is really all that's important; this is definitely an issue with portmidi, not Frescobaldi or the Python portmidi module):
Traceback (most recent call last):
File "/usr/lib/python2.7/dist-packages/frescobaldi_app/panels.py", line 136, in slotVisibilityChanged
self.widget()
File "/usr/lib/python2.7/dist-packages/frescobaldi_app/panels.py", line 129, in widget
w = self.createWidget()
File "/usr/lib/python2.7/dist-packages/frescobaldi_app/miditool/__init__.py", line 55, in createWidget
from . import widget
File "/usr/lib/python2.7/dist-packages/frescobaldi_app/miditool/widget.py", line 32, in <module>
import midihub
File "/usr/lib/python2.7/dist-packages/frescobaldi_app/midihub.py", line 42, in <module>
portmidi.init()
File "/usr/lib/python2.7/dist-packages/frescobaldi_app/portmidi/__init__.py", line 102, in init
if _setup() and not _initalized:
File "/usr/lib/python2.7/dist-packages/frescobaldi_app/portmidi/__init__.py", line 272, in _setup
pypm = globals()['_do_import_' + name]()
File "/usr/lib/python2.7/dist-packages/frescobaldi_app/portmidi/__init__.py", line 320, in _do_import_ctypes
from . import ctypes_pypm
File "/usr/lib/python2.7/dist-packages/frescobaldi_app/portmidi/ctypes_pypm.py", line 9, in <module>
from .pm_ctypes import (
File "/usr/lib/python2.7/dist-packages/frescobaldi_app/portmidi/pm_ctypes.py", line 101, in <module>
libpm = CDLL(dll_name)
File "/usr/lib/python2.7/ctypes/__init__.py", line 365, in __init__
self._handle = _dlopen(self._name, mode)
OSError: /usr/lib/libportmidi.so.0: undefined symbol: snd_seq_event_input_pending
Status changed to 'Confirmed' because the bug affects multiple users.