Xojo 2019R1.1 macOS Ventura 13.6 DebuggerHook / DecodeMachOTraceback crash

I’ve got a large project which is under Xojo 2019r1.1 and I can’t immediately migrate it to a newer version of Xojo.

Within the past year, the IDE debugger has stopped working:

  • any breakpoint or exception crashes with the following stack trace:
Stack Trace

Thread 0 Crashed:: Dispatch queue: com.apple.main-thread
0 XojoFramework.dylib 0x1127717cd DecodeMachOTraceback(void const*, std::__1::basic_string<char, std::__1::char_traits, std::__1::allocator>&, unsigned long*) + 644
1 XojoFramework.dylib 0x112755a03 0x1125bf000 + 1665539
2 XojoFramework.dylib 0x112860cf9 std::__1::function<bool (long, long)>::operator()(long, long) const + 39
3 XojoFramework.dylib 0x112860cb2 StackContext::Crawl(StackBounds, std::__1::function<bool (long, long)>) const + 128
4 XojoFramework.dylib 0x11274f584 0x1125bf000 + 1639812
5 XojoFramework.dylib 0x11274cfb3 DSDelegate::DebuggerConnectionMessage(DebuggerPacketParser const&) + 17
6 XojoFramework.dylib 0x11274b3ef DebuggerConnection::ProcessMessage(std::__1::basic_string<char, std::__1::char_traits, std::__1::allocator>) + 67
7 XojoFramework.dylib 0x11281a48a TCPSocketConnection::SocketDataReceived(TCPSocket*) + 370
8 XojoFramework.dylib 0x1126d247f TCPSocket::FireEvents() + 123
9 XojoFramework.dylib 0x1126cf0a5 TCPSocketPosix::Poll() + 925
10 XojoFramework.dylib 0x112754176 0x1125bf000 + 1659254
11 XojoFramework.dylib 0x112753f8f DebuggerHook + 836

  • this only happens with one of my largest projects. Smaller projects work fine
  • this is on macOS ventura 13.6.3 (but started earlier, perhaps on 13.5 or 13.6 ?)
  • running on an Intel cpu (i9) with 64 bit intel builds.
  • IDE / clearing caches: no change.
  • doesn’t matter where the breakpoint is (App.open, or deep in nested code: always crashes)
  • I’ve seen this same crash before, but it was perhaps 1% of the time; what’s new is that it’s now happening 100% of the time with this one project.


  • is anyone else seeing this?
  • I wonder if there’s a way to hack in a newer version of the Xojo debugger library or some other way of fixing this?

I can’t help I’m afraid, but I don’t suppose it works any better if you use the “Break” command instead of a breakpoint? Far less helpful I know but if it works.

I was under the impression that Xojo2019r1.1 can’t compile under newer macOS for Desktop projects.

Can you use an older macOS?

Good question - you can run 2019 on more recent OSs with this hack:
See Big Sur prise? Bug Surprise? - #38 by Lars_Brennicke

	- Run the Xojo app at least once, so that Gatekeeper is out of the way and you can modify Xojo.
	- Quiz Xojo
	- Right-click the Xojo app and choose “Show package contents”.
	- find the file Contents/Resources/SDKStubs/macosx10.14/System/Library/Frameworks/AppKit.framework/AppKit.tbd
	- Open in BBEdit
	- Under “reexports”, you’ll see  ,/System/Library/PrivateFrameworks/UIFoundation.framework/Versions/A/UIFoundation
	- Simply remove this text (including he preceding comma). Don’t delete the closing bracket
	- Save the file.

Could I use an older OS? Yes, in theory. In practice, let’s assume it’s so impractical that I’m not willing to, for the sake of this thread.

Yes, that’s the only hack I have seen.
I have no experience with Stacks so I don’t know what that means or how to create another hack for Xojo2019r1.1.
I guess you can’t try Xojo2019r3.2.
I hope someone can give you an idea on how to fix your problem.

Could you run the IDE in a virtual machine running an older version of macOS?

  • VM : yes, I could use a VM of an older OS, but my app is very graphics-intensive and macOS VMs have poor GPU support, so that’s not ideal for my needs. I suppose if I get desperate, I could remote debug from an older OS to a newer OS?
  • the fact that the crash is project-specific is interesting - maybe I’m wrong, and it’s not the OS version but rather something I changed in my project in the last year or so? It might be a good test to (A) try to debug a much older version of my app in Ventura 13.6.3, and (B) try my newest app in an older OS.

Looks similar to this issue which is reported fixed as of 2022r3.2: Ventura and Xojo 2022r1.1 Debugging Crash - #4 by Ian_Kennedy

Yes, that’s what I meant.

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