[Openmcl-devel] ccl and macOS Mojave

[R. Matthew Emerson]

Hi everyone.

As you may know, there are some compatibility issues with CCL and macOS Mojave.

The symptom is that the Lisp will crash into the Lisp kernel debugger with a message like "sigreturn returned" (on 1.11.5) or else with a message like "unhandled exception 4".

The GitHub issue for this is https://github.com/Clozure/ccl/issues/146

I ran CCL under a debug kernel, and I got the message:

process dx86cl64[405] sigreturn token mismatch: received 0x7ffeefbff120 expected 0xb993f3f80d520774

I think this is because Mojave has code to detect the case where a sigreturn doesn't match up with a signal that the kernel delivered.  Ideally, I'd like to find some way to disable this for now, until I can come up with a way change CCL so that it isn't affected by this.

CCL currently does semi-naughty things like copying around signal contexts and calling sigreturn explicitly (rather than just falling off the end of a signal handler).

Any suggestions or tips would be appreciated.

-m