Hang when unloading plugin from FL Studio

[damyanp]

Version

25.06

Plugin type

CLAP

OS

Windows 11 (ARM64)

DAW / Host (if applicable)

FL Studio

Description

To repro:

• Launch FL Studio
• Drag the Cardinal plugin to the channel rack
• Delete the Channel

At this point FL Studio hangs, eventually Windows pops up a "FL Studio is not responding" dialog. This reproduces for me with CLAP, VST and VST3 versions of the plugin.

The reason I think this is when the plugin unloads is because if I have multiple Cardinal channels, then it only hangs when the last one is removed. Also, it hangs in the same way when I exit FL Studio.

[dromer]

Is see you are using Windows ARM, does this use some translation layer?
We don't have ARM builds for Windows, so maybe that's part of the issue?

[damyanp]

Possibly - I'll have a go at getting a native ARM build - although there isn't a native FL Studio for ARM either, which makes me wonder if the problem actually exists there.

In a debugger, none of the threads seem to be inside Cardinal - and the main thread is stuck inside something that looks like OpenGLOn12 is waiting on an event or something. I'm assuming that if the Cardinal window isn't being displayed then it won't be issuing any GL API calls?

I'll keep digging - the repro does seem pretty consistent, and only seems to impact the combination of FL Studio & Cardinal.

[damyanp]

It doesn't seem to hang when loaded / unloaded from Carla. This may be a FL Studio issue.