MacOS Unity crash with Eye module during workshop

[leonsbe]

(happened during workshop)

Crash every time I end the Play mode.

Context: collider and layer of boxes set up, tried to show gaze visualization (not showing up, then when stopping Play mode: crash)

BugReportOnCrash.txt

When pasting to AI, it says: when you leave Play mode (thread 0 is sitting in PlayerLoopController::ExitPlayMode), Mono's garbage collector eventually runs the finalizer on the C# wrapper object for an LSL outlet, which calls lsl_destroy_outlet. libmalloc then aborts because the pointer being freed "was not allocated" — a classic double-free / mismatched free. The outlet is being destroyed twice, or freed across a module boundary that allocated it differently.

[eioe]

thx, @leonsbe ! That's very helpful.
We'll take a look.
Note for my future self: It's probably the EyeOutlet which causes the issue.
@leonsbe : if you want to (help) test this hypothesis at some point, you could delete the Eye-LslStreamer prefab from the EDIA-Eye-Manager GameObject in the scene which causes the problems, and try if it then runs without problems.

[thefirstfloor]

Hi @leonsbe

Thanks for the detailed report and crash log.
We researched it further, cause: the EyeOutlet creates its LSL StreamOutlet in Start() but never disposes it. Since StreamOutlet is a SafeHandle, the native object then gets freed by the GC finalizer instead of deterministically — at an unpredictable moment, off the main thread, during Unity's Play-mode teardown. That double-frees the native pointer, which macOS' allocator turns into a hard crash ("pointer being freed was not allocated"). On Windows the same invalid free stays latent, so it only surfaced on your Mac.

Fix: dispose the outlet in OnDestroy() so it's freed once, on the main thread. I've attached both updated scripts:
EyeOutlet.cs — this is the one behind your crash; replacing it should fix it.
BaseOutlet.cs — same fix applied to the shared base class, so the other outlet types (Marker/PosRot/…) can't hit the same issue. Optional for your test, but good to include.

We are hoping you could drop these in and enter/exit Play mode a few times on the Mac to confirm it no longer crashes?
This fix is on our internal upgrade branch atm and not pushed yet — testing it in your setup first.
That would really help us. 🙏🏼

ScriptFixes.zip