To see the Bug Report:

https://sourceforge.net/tracker/?func=detail&atid=104932&aid=3527375&group_id=4932

The answer from Rosegarden:

The backtrace seems like it agrees with what you describe.
ladspa_guitarix.so was doing some glibmm call which in turn called into
glib. Looks like g_private_replace() decided to abort(). So it may be
that glib/glibmm was updated on your system and there's a bug in one of
those.

I would try to fix it by first building and installing the latest guitarix
from sourceforge. If that doesn't work, try building and installing the
latest glib/glibmm. Might be tricky, though. Can you go back to the older
versions that worked?

Reporting this to your distro might also be helpful. They might already be
aware of a problem with one of their patches.

Most of audio programs in arch-linux (I think its the same at other distros) were provided from the community, here AUR. This is in one hand  positive and innovative. But it brings on the other side instability, like in our case and we are in a production.

My questions are how can i find older versions of this programs (glib/glibmm/guitarix) until the bug is fixed or how I can handle in future a "last best system" ?

Thanks a lot,

Yosef