HI guys, as soon I add Qmidiarp lv2 plugin to a track, Ardour crashes. It happens with precompiled version for Opensuse but also with the demo version. Qmidiarp works standalone.
Starting Ardour from a terminal, does not give useful information.
Thanks,
Daniele.
same problem here. any news?
Not here, still unusable 
At this point the most likely cause is an issue with the plugin to be honest. The name kinda gives a clue it likely involves Qt, which is already a warning sign honestly for a plugin (Fine for standalone options). The next debugging step would be to capture a stack trace and for the developer to identify what the issue is, but I would likely suggest finding a different arpeggiator or using it standalone.
SeabladeIndeed, there is an open bug report from March 2018 with this comment from one of the developers:
“qmidiarp as an application has been using Qt ever since, so the module GUIs are also Qt.”
Someone posted a comment about a day ago indicating that the latest source still builds with shared Qt libraries, this plugin will need to use a static build so that it is fully self-contained (which will possibly make the plugin executable very large depending on how much of the Qt libraries it needs to statically link).
A plugin should not tear down the whole daw. They should be isolated/sandboxes.
Sandboxing comes at a very high cost and significantly limits the number of plugins and tracks.
For the long story and math see https://ardour.org/plugins-in-process.html
Also when a plugin crashes there will be an audible artifact, so that’s game over already.