bug#45658: Infinite loop in run loop on macOS

[Jimmy Yuen Ho Wong]

I haven't seen this for quite some time now, but then I've switched to emacs 28 
some time ago too. I'm not sure if it's still a problem on emacs 27.

> On 20 Oct 2021, at 9:24 pm, Alan Third <alan@idiocy.org> wrote:
> On Wed, Oct 20, 2021 at 10:02:23AM +0800, Po Lu wrote:
>> Alan Third <alan@idiocy.org> writes:
>> 
>>> ns_send_appdefined somewhere. Can you switch to the thread that's
>>> running fd_handler and see what it's doing? There are only two
>>> branches, so it should be easy to work out which one is in use.
>> 
>>>>    frame #8: 0x00007fff2d14c039 AppKit`_DPSNextEvent + 883
>>>>    frame #9: 0x00007fff2d14a880 AppKit`-[NSApplication(NSEvent)
>>>> _nextEventMatchingEventMask:untilDate:inMode:dequeue:] + 1352
>>>>    frame #10: 0x00007fff2d13c58e AppKit`-[NSApplication run] + 658
>>>>    frame #11: 0x000000010036c5fa Emacs`-[EmacsApp
>>>> run](self=0x000000010525e180, _cmd="run") at nsterm.m:5602:9
>>>>    frame #12: 0x000000010036a8eb Emacs`ns_select(nfds=30,
>>>> readfds=0x00007ffeefbfd1f0, writefds=0x00007ffeefbfd170,
>>>> exceptfds=0x0000000000000000, timeout=0x00007ffeefbfd148,
>>>> sigmask=0x0000000000000000) at nsterm.m:4690:3
>> 
>> Does it also make sense for this to occur on GNUstep?  I have just seen
>> a very similar bug there, but I lost the backtrace :(
> 
> It doesn't make any sense to me for it to happen anywhere. ;)
> 
> If it happens on macOS I don't see why it shouldn't happen on GNUstep,
> unless it's a bug in Cocoa and not in GNUstep. I wasn't able to
> replicate the crash and I don't have any real clue what was causing it
> for Jimmy.
> -- 
> Alan Third