topic Re: Crash in destructor of DG::Browser in Archicad C++ API

Crash in destructor of DG::Browser

andrewille — Tue, 17 Sep 2024 09:25:22 GMT

Hello,

I am experiencing random crashes in the destructor of my class, which extends the DG::Browser class. The weird thing is that I do not override the destructor. So I think this might be an issue of ArchiCAD 26.

Can somebody relate or has a solution for this? Thanks.

Re: Crash in destructor of DG::Browser

andrewille — Thu, 27 Jun 2024 10:51:29 GMT

Still occuring in AC27 5003 INT FULL. I uploaded the log files.

We really need this to be fixed @Viktor Kovacs @Akos Somorjai

Re: Crash in destructor of DG::Browser

Akos Somorjai — Thu, 27 Jun 2024 11:04:42 GMT

Hi Andre,

Have you submitted this as a bug report? If so, could you please tell me the bug ID you received? This would give me more information.

Thanks, Akos

Re: Crash in destructor of DG::Browser

andrewille — Thu, 27 Jun 2024 12:51:43 GMT

Hi @Akos Somorjai ,

here is the report ID: AC26-2024-06-27-12-29-23-7213

It is happening randomly on shutdown of ArchiCAD, in the destructor of DG::Browser. I reproduced it in AC26 right now because it happens more often so it was easier to trigger it.

Re: Crash in destructor of DG::Browser

Akos Somorjai — Thu, 27 Jun 2024 13:11:36 GMT

Hi Andre,

Thanks, that's very useful! I forwarded your request to a developer who knows more about this.

Re: Crash in destructor of DG::Browser

Akos Somorjai — Tue, 02 Jul 2024 07:28:27 GMT

Hi Andre,

We haven't found the exact cause – yet. How are you destroying the DG::Browser instance?

Thanks, Akos

Re: Crash in destructor of DG::Browser

andrewille — Tue, 02 Jul 2024 09:50:11 GMT

Hi Akos,
here is a brief snippet of the hierarchy:

class LicenseManagerNew { static LicenseManagerNew *instance; // singleton class OAuthPalette loginPalette; ~LicenseManagerNew(); // destructor implemented, but does not explicitly destroy loginPalette } class OAuthPalette : DG::Palette { OAuthBrowser browser; // no destructor implemented } class OAuthBrowser : DG::Browser { // no destructor implemented }

The crash happens only sometimes on shutdown on ArchiCAD. As you can see, LicenseManagerNew is a singleton class which gets destroyed automatically. The destructor of it does not explicitly destroy the other components I showed, but it happens implicitly on the end of the destructor (automatically). I have not implemented any other destructors, the exception is thrown internally in the DG::Browser's destructor. I haven't recognized any pattern how to trigger it exactly, but before exiting, the browser was used and a connection might still be open (if HTTP/2 if supported, at least).

Kind Regards

André

Re: Crash in destructor of DG::Browser

andrewille — Thu, 04 Jul 2024 12:37:55 GMT

@Akos Somorjai

Any news on this? Have you sent them the stacktrace I uploaded?

Re: Crash in destructor of DG::Browser

Akos Somorjai — Thu, 04 Jul 2024 13:52:05 GMT

Hi André,

Just two "maybe" ideas so far:

- for some reason, the creation of the browser fails – do you receive any error?

- memory overwrite in BIMmTool -- have you run the add-on with any memory checks?

Best, Akos

Re: Crash in destructor of DG::Browser

andrewille — Fri, 05 Jul 2024 12:47:52 GMT

Hi Akos,

the browser was created and worked fine. It's just its shutdown that causes issues. The access violation is triggered in the ArchiCAD code (as seen in the stacktrace). It tries reading a null pointer (as seen in the log). I don't think it would access any of the pointers managed by BIMmTool, would it?

To me this looks like some race condition. As I said, the destruction happens when the singleton class gets destroyed, which might happen very late. It might be so late that ArchiCAD has already freed some memory it needs for the destruction.

As a workaround, I will try to manually destroy the DG::Browser earlier now, i.e. when the project is closed. It is hard to tell whether this fixes it because it occurs so randomly. I will keep you updated.

Kind Regards

André

Re: Crash in destructor of DG::Browser

Akos Somorjai — Fri, 05 Jul 2024 13:17:13 GMT

Hi André,

The race condition looks promising; some garbage collection may have destroyed the browser control.

Let me know if this works.

Best, Akos

Re: Crash in destructor of DG::Browser

dushyant — Sat, 13 Sep 2025 06:57:36 GMT

@andrewille - Hi, were you able to solve this?

Re: Crash in destructor of DG::Browser

andrewille — Sat, 13 Sep 2025 09:30:41 GMT

Hello @dushyant ,

yes, indeed. I found a workaround that works for me in all tested versions of ArchiCad. You need to manually destroy the DG::Browser instance earlier. I hooked the method when a project is closed to do it. Maybe it would also work with the shutdown hook. Just do it early enough so the rest of Archicad is still initialized and then you won't get any race conditions anymore.

Re: Crash in destructor of DG::Browser

dushyant — Sat, 13 Sep 2025 10:58:41 GMT

Okay, great that you were able to fix it!
Could you please share where exactly you destroy the DG::Browser instance so that is early enough to avoid the crash?
Just to confirm - in your case, did you explicitly call ~OAuthBrowser() or used some other way to destroy it?

Thanks.

Re: Crash in destructor of DG::Browser

dushyant — Sun, 14 Sep 2025 06:57:16 GMT

I was able to fix it by destroying the browser instance in FreeData().

Thanks.