Hi all,

I usually use Emacs 27 (AKA `master`). I upgraded to the latest Mojave 
beta (1 week until GM I believe, I was eager!)

Thanks Alan for providing the patch, I took the patch (which you said 
was based on emacs-26) and "updated"
(used the `wiggle` command for the hunks that wouldn't apply, I've never 
really meddled with Objective-C before and
I've never really updated a patch before when there's rejected hunks, so 
please excuse any ignorance you pick up on. :-)

The patch builds and launches Emacs successfully! (Thanks again Alan)

However, just thought I'd mention that after some time (5-10 minutes of 
idling, and just now it crashed during launch) I get the following:

Note that I *believe* I've compiled Emacs with debugging symbols and no 
optimisation, feel free to correct me if not.

Hopefully the below output is helpful to someone. This might even be a 
bug in Mojave and one of the core libraries, but I haven't had
this with other applications:

I can reproduce the issue within a maximum of 10 minutes, whether typing 
or not.

It's likely worthy to note that this happened also with the emacs-26 
branch, commit d4fa83baf5462cfcf61ebbb8c0a0ec584d11c39a,
under the same circumstances, and with the attached patch applied.

Feel free to shout at me to submit this as a new bug, I couldn't find 
which email makes a new one. :-(

The below happens on commit 75d9a55fae1c484aa6d213064931bfe3b65cf5dd on 
the master branch.

```
objc[95306]: Invalid or prematurely-freed autorelease pool 0x103e60378.
Process 95306 stopped
* thread #1, queue = 'com.apple.main-thread', stop reason = signal 
SIGABRT
     frame #0: 0x00007fff7679b01e 
libsystem_kernel.dylib`__abort_with_payload + 10
libsystem_kernel.dylib`__abort_with_payload:
->  0x7fff7679b01e <+10>: jae    0x7fff7679b028            ; <+20>
     0x7fff7679b020 <+12>: movq   %rax, %rdi
     0x7fff7679b023 <+15>: jmp    0x7fff7677de67            ; 
cerror_nocancel
     0x7fff7679b028 <+20>: retq
Target 0: (Emacs) stopped.
(lldb) bt all
* thread #1, queue = 'com.apple.main-thread', stop reason = signal 
SIGABRT
   * frame #0: 0x00007fff7679b01e 
libsystem_kernel.dylib`__abort_with_payload + 10
     frame #1: 0x00007fff76796561 
libsystem_kernel.dylib`abort_with_payload_wrapper_internal + 82
     frame #2: 0x00007fff7679650f 
libsystem_kernel.dylib`abort_with_reason + 22
     frame #3: 0x00007fff75579674 libobjc.A.dylib`_objc_fatalv(unsigned 
long long, unsigned long long, char const*, __va_list_tag*) + 108
     frame #4: 0x00007fff75579526 libobjc.A.dylib`_objc_fatal(char 
const*, ...) + 135
     frame #5: 0x00007fff7556bd73 libobjc.A.dylib`(anonymous 
namespace)::AutoreleasePoolPage::pop(void*) + 957
     frame #6: 0x00007fff46c2d232 AppKit`-[NSView(NSInternal) 
_recursive:displayRectIgnoringOpacity:inContext:shouldChangeFontReferenceColor:stopAtLayerBackedViews:] 
+ 3454
     frame #7: 0x00007fff46c2c4a2 AppKit`__46-[NSView(NSLayerKitGlue) 
drawLayer:inContext:]_block_invoke + 192
     frame #8: 0x00007fff46c2c201 AppKit`-[NSView(NSLayerKitGlue) 
_drawViewBackingLayer:inContext:drawingHandler:] + 1769
     frame #9: 0x00007fff54540aaf QuartzCore`CABackingStoreUpdate_ + 577
     frame #10: 0x00007fff545a2325 
QuartzCore`___ZN2CA5Layer8display_Ev_block_invoke + 53
     frame #11: 0x00007fff5453fc90 QuartzCore`-[CALayer _display] + 1839
     frame #12: 0x00007fff46c2b75a AppKit`_NSBackingLayerDisplay + 531
     frame #13: 0x00007fff46c0fcc9 AppKit`-[_NSViewBackingLayer display] 
+ 811
     frame #14: 0x00007fff46c0f949 AppKit`_NSBackingLayerDisplayIfNeeded 
+ 40
     frame #15: 0x00007fff46c0f2a4 AppKit`-[NSView displayIfNeeded] + 
130
     frame #16: 0x0000000100026514 Emacs`echo_area_display + 593
     frame #17: 0x00000001000261ca Emacs`message3_nolog + 393
     frame #18: 0x0000000100025fe3 Emacs`message3 + 399
     frame #19: 0x0000000100106a03 Emacs`Fmessage + 67
     frame #20: 0x000000010010f525 Emacs`Ffuncall + 665
     frame #21: 0x0000000100145e02 Emacs`exec_byte_code + 1486
     frame #22: 0x0000000100110040 Emacs`funcall_lambda + 648
     frame #23: 0x000000010010f4c2 Emacs`Ffuncall + 566
     frame #24: 0x000000010010f704 Emacs`funcall_nil + 9
     frame #25: 0x000000010010f6a0 Emacs`run_hook_with_args + 198
     frame #26: 0x000000010010f58b Emacs`Frun_hooks + 60
     frame #27: 0x000000010010f525 Emacs`Ffuncall + 665
     frame #28: 0x0000000100145e02 Emacs`exec_byte_code + 1486
     frame #29: 0x000000010010f4c2 Emacs`Ffuncall + 566
     frame #30: 0x0000000100145e02 Emacs`exec_byte_code + 1486
     frame #31: 0x000000010010f4c2 Emacs`Ffuncall + 566
     frame #32: 0x0000000100145e02 Emacs`exec_byte_code + 1486
     frame #33: 0x000000010010f4c2 Emacs`Ffuncall + 566
     frame #34: 0x0000000100145e02 Emacs`exec_byte_code + 1486
     frame #35: 0x000000010010f4c2 Emacs`Ffuncall + 566
     frame #36: 0x0000000100145e02 Emacs`exec_byte_code + 1486
     frame #37: 0x000000010010f4c2 Emacs`Ffuncall + 566
     frame #38: 0x0000000100145e02 Emacs`exec_byte_code + 1486
     frame #39: 0x000000010010ee62 Emacs`apply_lambda + 369
     frame #40: 0x000000010010c484 Emacs`eval_sub + 845
     frame #41: 0x000000010012d294 Emacs`readevalloop + 1773
     frame #42: 0x000000010012d502 Emacs`Feval_buffer + 368
     frame #43: 0x000000010010fcfe Emacs`funcall_subr + 367
     frame #44: 0x000000010010f525 Emacs`Ffuncall + 665
     frame #45: 0x0000000100145e02 Emacs`exec_byte_code + 1486
     frame #46: 0x0000000100110040 Emacs`funcall_lambda + 648
     frame #47: 0x000000010010f4c2 Emacs`Ffuncall + 566
     frame #48: 0x000000010010f9d1 Emacs`call4 + 58
     frame #49: 0x000000010012b845 Emacs`Fload + 1373
     frame #50: 0x000000010010fcfe Emacs`funcall_subr + 367
     frame #51: 0x000000010010f525 Emacs`Ffuncall + 665
     frame #52: 0x0000000100145e02 Emacs`exec_byte_code + 1486
     frame #53: 0x000000010010f4c2 Emacs`Ffuncall + 566
     frame #54: 0x0000000100145e02 Emacs`exec_byte_code + 1486
     frame #55: 0x000000010010f4c2 Emacs`Ffuncall + 566
     frame #56: 0x0000000100145e02 Emacs`exec_byte_code + 1486
     frame #57: 0x000000010010ee62 Emacs`apply_lambda + 369
     frame #58: 0x000000010010c484 Emacs`eval_sub + 845
     frame #59: 0x000000010010ec69 Emacs`Feval + 96
     frame #60: 0x000000010010dffd Emacs`internal_condition_case + 87
     frame #61: 0x00000001000b17be Emacs`top_level_1 + 45
     frame #62: 0x000000010010db85 Emacs`internal_catch + 74
     frame #63: 0x00000001000a4a90 Emacs`command_loop + 141
     frame #64: 0x00000001000a49c1 Emacs`recursive_edit_1 + 115
     frame #65: 0x00000001000a4bdd Emacs`Frecursive_edit + 226
     frame #66: 0x00000001000a3aa9 Emacs`main + 5211
     frame #67: 0x00007fff76645085 libdyld.dylib`start + 1
     frame #68: 0x00007fff76645085 libdyld.dylib`start + 1
   thread #2
     frame #0: 0x00007fff7677f5be 
libsystem_kernel.dylib`__workq_kernreturn + 10
     frame #1: 0x6874656d00000000
     frame #2: 0x00007fff76836415 libsystem_pthread.dylib`start_wqthread 
+ 13
   thread #3
     frame #0: 0x00007fff7677f5be 
libsystem_kernel.dylib`__workq_kernreturn + 10
     frame #1: 0x00007fff76836641 
libsystem_pthread.dylib`_pthread_wqthread + 446
     frame #2: 0x00007fff76836415 libsystem_pthread.dylib`start_wqthread 
+ 13
   thread #4, name = 'gmain'
     frame #0: 0x00007fff76784e82 libsystem_kernel.dylib`__select + 10
     frame #1: 0x0000000100a083da libglib-2.0.0.dylib`g_poll + 405
     frame #2: 0x00000001009fc123 
libglib-2.0.0.dylib`g_main_context_iterate + 340
     frame #3: 0x00000001009fc1d1 
libglib-2.0.0.dylib`g_main_context_iteration + 55
     frame #4: 0x00000001009fd2b0 libglib-2.0.0.dylib`glib_worker_main + 
30
     frame #5: 0x0000000100a1dcb7 libglib-2.0.0.dylib`g_thread_proxy + 
90
     frame #6: 0x00007fff7683733d libsystem_pthread.dylib`_pthread_body 
+ 126
     frame #7: 0x00007fff7683a2a7 libsystem_pthread.dylib`_pthread_start 
+ 70
     frame #8: 0x00007fff76836425 libsystem_pthread.dylib`thread_start + 
13
   thread #5
     frame #0: 0x00007fff7677f5be 
libsystem_kernel.dylib`__workq_kernreturn + 10
     frame #1: 0x00007fff76836721 
libsystem_pthread.dylib`_pthread_wqthread + 670
     frame #2: 0x00007fff76836415 libsystem_pthread.dylib`start_wqthread 
+ 13
   thread #7
     frame #0: 0x00007fff76784e82 libsystem_kernel.dylib`__select + 10
     frame #1: 0x000000010017c408 Emacs`-[EmacsApp fd_handler:] + 214
     frame #2: 0x00007fff4b902234 Foundation`__NSThread__start__ + 1218
     frame #3: 0x00007fff7683733d libsystem_pthread.dylib`_pthread_body 
+ 126
     frame #4: 0x00007fff7683a2a7 libsystem_pthread.dylib`_pthread_start 
+ 70
     frame #5: 0x00007fff76836425 libsystem_pthread.dylib`thread_start + 
13
   thread #9, name = 'com.apple.NSEventThread'
     frame #0: 0x00007fff7677dc2a libsystem_kernel.dylib`mach_msg_trap + 
10
     frame #1: 0x00007fff7677e174 libsystem_kernel.dylib`mach_msg + 60
     frame #2: 0x00007fff495ad05e 
CoreFoundation`__CFRunLoopServiceMachPort + 337
     frame #3: 0x00007fff495ac5ad CoreFoundation`__CFRunLoopRun + 1654
     frame #4: 0x00007fff495abce4 CoreFoundation`CFRunLoopRunSpecific + 
463
     frame #5: 0x00007fff46b0b581 AppKit`_NSEventThread + 160
     frame #6: 0x00007fff7683733d libsystem_pthread.dylib`_pthread_body 
+ 126
     frame #7: 0x00007fff7683a2a7 libsystem_pthread.dylib`_pthread_start 
+ 70
     frame #8: 0x00007fff76836425 libsystem_pthread.dylib`thread_start + 
13
(lldb)
```