SIGSEGV when switching between window layouts

[kidonng]

Describe the bug
kitty crashes when switching between window layouts for a couple of times.

To Reproduce
Steps to reproduce the behavior:

1. Launch kitty
2. Open several windows (4 is enough)
3. Press ctrl+shift+l several times to switch between window layouts
4. After some time kitty will crash

Screenshots
N/A

Environment details

Press Ctrl+Shift+F6 in kitty, to copy debug output about kitty and its
configuration to the clipboard and paste it here. 

On older versions of kitty, run kitty --debug-config instead

(I don't know why, pressing Ctrl+Shift+F6 doesn't do anything)

Additional context
Reproduced with kitty --config NONE.

Crash report with make debug:

Process:               kitty [29682]
Path:                  /private/var/folders/*/kitty
Identifier:            kitty
Version:               0
Code Type:             X86-64 (Native)
Parent Process:        fish [24177]
Responsible:           kitty [13168]
User ID:               501

Date/Time:             2021-06-12 15:16:02.728 +0800
OS Version:            macOS 11.5 (20G5033c)
Report Version:        12
Anonymous UUID:        1F92AAD2-E3DE-D617-EE38-E71819508A69

Sleep/Wake UUID:       EAA1F16B-0E51-4F1A-8B6B-01FF4EAF7E97

Time Awake Since Boot: 18000 seconds
Time Since Wake:       18000 seconds

System Integrity Protection: disabled

Crashed Thread:        0  Dispatch queue: com.apple.main-thread

Exception Type:        EXC_BAD_ACCESS (SIGSEGV)
Exception Codes:       KERN_INVALID_ADDRESS at 0x0000000000000018
Exception Note:        EXC_CORPSE_NOTIFY

Termination Signal:    Segmentation fault: 11
Termination Reason:    Namespace SIGNAL, Code 0xb
Terminating Process:   exc handler [29682]

External Modification Warnings:
Thread creation by external task.

VM Regions Near 0x18:
--> 
    __TEXT                      1069a0000-1069a4000    [   16K] r-x/r-x SM=COW  /var/folders/*/kitty.app/Contents/MacOS/kitty

Thread 0 Crashed:: Dispatch queue: com.apple.main-thread
0   fast_data_types.so            	0x00000001071de489 screen_detect_url + 57 (screen.c:2170)
1   fast_data_types.so            	0x00000001071a370e detect_url + 14 (mouse.c:311)
2   fast_data_types.so            	0x00000001071a36e8 mouse_open_url + 24 (mouse.c:408)
3   fast_data_types.so            	0x00000001071f07ed click_mouse_url + 189 (state.c:995)
4   fast_data_types.so            	0x00000001071ebe6b pyclick_mouse_url + 75 (state.c:1012)
5   org.python.python             	0x0000000106a660c2 cfunction_call + 90
6   org.python.python             	0x0000000106a1b6da _PyObject_MakeTpCall + 129
7   org.python.python             	0x0000000106b13cbd call_function + 270
8   org.python.python             	0x0000000106b11562 _PyEval_EvalFrameDefault + 45384
9   org.python.python             	0x0000000106a1c240 _PyFunction_Vectorcall + 192
10  org.python.python             	0x0000000106b13c53 call_function + 164
11  org.python.python             	0x0000000106b11489 _PyEval_EvalFrameDefault + 45167
12  org.python.python             	0x0000000106a1c240 _PyFunction_Vectorcall + 192
13  org.python.python             	0x0000000106a1efbb method_vectorcall + 481
14  org.python.python             	0x0000000106b1175e _PyEval_EvalFrameDefault + 45892
15  org.python.python             	0x0000000106b052d6 _PyEval_EvalCode + 403
16  org.python.python             	0x0000000106a1c2f8 _PyFunction_Vectorcall + 376
17  org.python.python             	0x0000000106a1ee7a method_vectorcall + 160
18  org.python.python             	0x0000000106b13c53 call_function + 164
19  org.python.python             	0x0000000106b11612 _PyEval_EvalFrameDefault + 45560
20  org.python.python             	0x0000000106a1c240 _PyFunction_Vectorcall + 192
21  org.python.python             	0x0000000106a1ef47 method_vectorcall + 365
22  org.python.python             	0x0000000106a1c7f4 _PyObject_CallFunctionVa + 163
23  org.python.python             	0x0000000106a1d0fe _PyObject_CallMethod_SizeT + 196
24  fast_data_types.so            	0x00000001071a389e dispatch_mouse_event + 286 (mouse.c:153)
25  fast_data_types.so            	0x00000001071a3771 send_pending_click_to_window + 65 (mouse.c:428)
26  fast_data_types.so            	0x00000001071eb6c8 send_pending_click_to_window_id + 200 (state.c:555)
27  glfw-cocoa.so                 	0x0000000107faa94e __schedule_timer_block_invoke + 62 (cocoa_init.m:720)
28  com.apple.Foundation          	0x00007fff21250e0f __NSFireTimer + 67
29  com.apple.CoreFoundation      	0x00007fff2049b279 __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ + 20
30  com.apple.CoreFoundation      	0x00007fff2049ad6d __CFRunLoopDoTimer + 927
31  com.apple.CoreFoundation      	0x00007fff2049a8ca __CFRunLoopDoTimers + 307
32  com.apple.CoreFoundation      	0x00007fff204814a3 __CFRunLoopRun + 1988
33  com.apple.CoreFoundation      	0x00007fff2048061c CFRunLoopRunSpecific + 563
34  com.apple.HIToolbox           	0x00007fff28761a83 RunCurrentEventLoopInMode + 292
35  com.apple.HIToolbox           	0x00007fff287617e5 ReceiveNextEventCommon + 587
36  com.apple.HIToolbox           	0x00007fff28761583 _BlockUntilNextEventMatchingListInModeWithFilter + 70
37  com.apple.AppKit              	0x00007fff22c806f2 _DPSNextEvent + 864
38  com.apple.AppKit              	0x00007fff22c7eec5 -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] + 1364
39  com.apple.AppKit              	0x00007fff22c71239 -[NSApplication run] + 586
40  glfw-cocoa.so                 	0x0000000107faa631 _glfwPlatformRunMainLoop + 81 (cocoa_init.m:685)
41  glfw-cocoa.so                 	0x0000000107fa36d2 glfwRunMainLoop + 18 (init.c:352)
42  fast_data_types.so            	0x000000010718b82d run_main_loop + 13 (glfw.c:1399)
43  fast_data_types.so            	0x0000000107122b5b main_loop + 59 (child-monitor.c:1049)
44  org.python.python             	0x0000000106a27acd method_vectorcall_NOARGS + 99
45  org.python.python             	0x0000000106b13c53 call_function + 164
46  org.python.python             	0x0000000106b11489 _PyEval_EvalFrameDefault + 45167
47  org.python.python             	0x0000000106b052d6 _PyEval_EvalCode + 403
48  org.python.python             	0x0000000106a1c2f8 _PyFunction_Vectorcall + 376
49  org.python.python             	0x0000000106b13c53 call_function + 164
50  org.python.python             	0x0000000106b11562 _PyEval_EvalFrameDefault + 45384
51  org.python.python             	0x0000000106b052d6 _PyEval_EvalCode + 403
52  org.python.python             	0x0000000106a1c2f8 _PyFunction_Vectorcall + 376
53  org.python.python             	0x0000000106a1b907 _PyObject_FastCallDictTstate + 87
54  org.python.python             	0x0000000106a8878e slot_tp_call + 187
55  org.python.python             	0x0000000106a1b6da _PyObject_MakeTpCall + 129
56  org.python.python             	0x0000000106b13cbd call_function + 270
57  org.python.python             	0x0000000106b11562 _PyEval_EvalFrameDefault + 45384
58  org.python.python             	0x0000000106a1c240 _PyFunction_Vectorcall + 192
59  org.python.python             	0x0000000106b13c53 call_function + 164
60  org.python.python             	0x0000000106b11562 _PyEval_EvalFrameDefault + 45384
61  org.python.python             	0x0000000106a1c240 _PyFunction_Vectorcall + 192
62  org.python.python             	0x0000000106b13c53 call_function + 164
63  org.python.python             	0x0000000106b11562 _PyEval_EvalFrameDefault + 45384
64  org.python.python             	0x0000000106a1c240 _PyFunction_Vectorcall + 192
65  org.python.python             	0x0000000106b13c53 call_function + 164
66  org.python.python             	0x0000000106b11562 _PyEval_EvalFrameDefault + 45384
67  org.python.python             	0x0000000106b052d6 _PyEval_EvalCode + 403
68  org.python.python             	0x0000000106b0004f builtin_exec + 389
69  org.python.python             	0x0000000106a66a43 cfunction_vectorcall_FASTCALL + 95
70  org.python.python             	0x0000000106b13c53 call_function + 164
71  org.python.python             	0x0000000106b11562 _PyEval_EvalFrameDefault + 45384
72  org.python.python             	0x0000000106b052d6 _PyEval_EvalCode + 403
73  org.python.python             	0x0000000106a1c2f8 _PyFunction_Vectorcall + 376
74  org.python.python             	0x0000000106b13c53 call_function + 164
75  org.python.python             	0x0000000106b11562 _PyEval_EvalFrameDefault + 45384
76  org.python.python             	0x0000000106b052d6 _PyEval_EvalCode + 403
77  org.python.python             	0x0000000106a1c2f8 _PyFunction_Vectorcall + 376
78  org.python.python             	0x0000000106b83fd0 pymain_run_module + 212
79  org.python.python             	0x0000000106b83ac8 pymain_run_python + 479
80  org.python.python             	0x0000000106b838ad Py_RunMain + 23
81  org.python.python             	0x0000000106b84bca pymain_main + 35
82  org.python.python             	0x0000000106b84ba1 Py_Main + 42
83  kitty                         	0x00000001069a3c0c main + 1116
84  libdyld.dylib                 	0x00007fff203a4f5d start + 1

Thread 1:
0   libsystem_pthread.dylib       	0x00007fff20385420 start_wqthread + 0

Thread 2:
0   libsystem_kernel.dylib        	0x00007fff203542ba mach_msg_trap + 10
1   libsystem_kernel.dylib        	0x00007fff2035462c mach_msg + 60
2   libsystem_kernel.dylib        	0x00007fff2037399b thread_suspend + 80
3   ???                           	0x0000000108103877 0 + 4430248055

Thread 3:: com.apple.NSEventThread
0   libsystem_kernel.dylib        	0x00007fff203542ba mach_msg_trap + 10
1   libsystem_kernel.dylib        	0x00007fff2035462c mach_msg + 60
2   com.apple.CoreFoundation      	0x00007fff20482b2f __CFRunLoopServiceMachPort + 316
3   com.apple.CoreFoundation      	0x00007fff2048120f __CFRunLoopRun + 1328
4   com.apple.CoreFoundation      	0x00007fff2048061c CFRunLoopRunSpecific + 563
5   com.apple.AppKit              	0x00007fff22e0668a _NSEventThread + 124
6   libsystem_pthread.dylib       	0x00007fff203898fc _pthread_start + 224
7   libsystem_pthread.dylib       	0x00007fff20385443 thread_start + 15

Thread 4:: KittyChildMon
0   libsystem_kernel.dylib        	0x00007fff2035a9ca poll + 10
1   fast_data_types.so            	0x00000001071234d9 io_loop + 457
2   libsystem_pthread.dylib       	0x00007fff203898fc _pthread_start + 224
3   libsystem_pthread.dylib       	0x00007fff20385443 thread_start + 15

Thread 5:: CVDisplayLink
0   libsystem_kernel.dylib        	0x00007fff20356cde __psynch_cvwait + 10
1   libsystem_pthread.dylib       	0x00007fff20389e7f _pthread_cond_wait + 1352
2   com.apple.CoreVideo           	0x00007fff272cdfe3 CVDisplayLink::waitUntil(unsigned long long) + 229
3   com.apple.CoreVideo           	0x00007fff272cd4ec CVDisplayLink::runIOThread() + 482
4   libsystem_pthread.dylib       	0x00007fff203898fc _pthread_start + 224
5   libsystem_pthread.dylib       	0x00007fff20385443 thread_start + 15

Thread 0 crashed with X86 Thread State (64-bit):
  rax: 0x0000000000000000  rbx: 0x0000000000000000  rcx: 0x00007fbdf67f60dc  rdx: 0x0000000000000017
  rdi: 0x00007fbdfc1a1000  rsi: 0x0000000000000017  rbp: 0x00007ffee9256bd0  rsp: 0x00007ffee9256b90
   r8: 0x0000000106d63930   r9: 0x0000000106c22040  r10: 0x00007ffee9256c30  r11: 0x00000001072b6c3c
  r12: 0x00007fbdfc1a1000  r13: 0x000000000000001e  r14: 0x0000000000000017  r15: 0x0000000000000000
  rip: 0x00000001071de489  rfl: 0x0000000000010246  cr2: 0x0000000000000018
  
Logical CPU:     0
Error Code:      0x00000004 (no mapping for user data read)
Trap Number:     14

Thread 0 instruction stream:
  5e 41 5f 5d c3 66 90 55-48 89 e5 31 c0 48 85 b7  ^A_].f.UH..1.H..
  a8 00 00 00 0f 95 c0 5d-c3 66 2e 0f 1f 84 00 00  .......].f......
  00 00 00 0f 1f 40 00 55-48 89 e5 41 57 41 56 41  .....@.UH..AWAVA
  55 41 54 53 48 83 ec 18-41 89 d6 41 89 f5 49 89  UATSH...A..A..I.
  fc 48 8b 05 67 bc 0d 00-48 8b 00 48 89 45 d0 c7  .H..g...H..H.E..
  45 cc 00 00 00 00 89 d6-e8 3a 01 00 00 48 89 c3  E........:...H..
 [48]8b 40 18 44 89 e9 48-8d 0c 49 66 83 7c 88 08  H.@.D..H..If.|..	<==
  00 74 16 4c 89 e7 44 89-ee 44 89 f2 e8 36 01 00  .t.L..D..D...6..
  00 41 b5 01 e9 d8 00 00-00 48 85 db 74 46 48 89  .A.......H..tFH.
  df 44 89 ee e8 7e 12 fc-ff 41 89 c7 3b 43 20 73  .D...~...A..;C s
  4b 41 8b 44 24 14 ff c8-44 39 f0 76 41 41 8d 76  KA.D$...D9.vAA.v
  01 4c 89 e7 e8 de 00 00-00 48 89 c7 e8 46 17 fc  .L.......H...F..
  
Thread 0 last branch register state not available.

[kovidgoyal]

Doesn't crash for me with those steps and according to the traceback you
posted the crash is happening while processing a mouse click. I have
made a commit that should prevent the crash in the traceback, please try
it.

[kidonng]

Sorry, I forgot to mention I also have to clicking around in order to reproduce the issues. The latest commit seems fine so far, thanks!

[kovidgoyal]

No worries, hopefully my commit fixes it.