Can you reproduce this threading bug?

[Jacob Carlborg]

On 2019-06-14 18:36, FeepingCreature wrote:
> Consider the following code:
> 
> void main()
> {
>      import core.thread : Thread;
> 
>      with (new Thread({ })) { isDaemon = true; start; }
> }
> 
> On Linux, this builds and runs. Most of the time. Maybe 99% of the time.
> 
> But if you run it in a loop:
> 
> while true; do ./test || break; done
> 
> You may see that it segfaults after a few seconds. At least, it does for 
> me on 2.080.0, Linux 4.18.0-20 x86_64.
> 
> This is obviously quite bad. Any ideas?

On macOS I get a mixture of the following:

Aborting from src/core/sync/mutex.d(149) Error: pthread_mutex_destroy 
failed.Abort trap: 6

Aborting from src/core/sync/mutex.d(149) Error: pthread_mutex_destroy 
failed.Segmentation fault: 11

Aborting from Segmentation fault: 11



Pretty easy to reproduce. But when I tried in a debugger I failed to 
reproduce the segfault. Although, here is what the crash reporter logged:

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

Exception Type:        EXC_CRASH (SIGABRT)
Exception Codes:       0x0000000000000000, 0x0000000000000000
Exception Note:        EXC_CORPSE_NOTIFY

Application Specific Information:
abort() called

Thread 0 Crashed:: Dispatch queue: com.apple.main-thread
0   libsystem_kernel.dylib        	0x00007fff4fe8cb66 __pthread_kill + 10
1   libsystem_pthread.dylib       	0x00007fff50057080 pthread_kill + 333
2   libsystem_c.dylib             	0x00007fff4fde81ae abort + 127
3   main                          	0x00000001033978e2 
_D4core8internal5abortQgFNbNiNfMAyaMQemZv + 262
4   main                          	0x0000000103394e73 thread_term + 259
5   main                          	0x00000001033a7268 rt_term + 88
6   main                          	0x00000001033a796c 
_D2rt6dmain211_d_run_mainUiPPaPUAAaZiZ6runAllMFZv + 208
7   main                          	0x00000001033a7848 
_D2rt6dmain211_d_run_mainUiPPaPUAAaZiZ7tryExecMFMDFZvZv + 36
8   main                          	0x00000001033a77a8 _d_run_main + 764
9   main                          	0x0000000103384e72 main + 34
10  libdyld.dylib                 	0x00007fff4fd3c015 start + 1

Thread 1:
0   main                          	0x0000000103394ab3 
_D4core6thread6Thread6removeFNbNiCQBgQBeQBaZv + 63
1   main                          	0x0000000103393922 thread_entryPoint 
+ 526
2   libsystem_pthread.dylib       	0x00007fff50054661 _pthread_body + 340
3   libsystem_pthread.dylib       	0x00007fff5005450d _pthread_start + 377
4   libsystem_pthread.dylib       	0x00007fff50053bf9 thread_start + 13

Thread 0 crashed with X86 Thread State (64-bit):
   rax: 0x0000000000000000  rbx: 0x00007fff88782380  rcx: 
0x00007ffeec87b158  rdx: 0x0000000000000000
   rdi: 0x0000000000000307  rsi: 0x0000000000000006  rbp: 
0x00007ffeec87b190  rsp: 0x00007ffeec87b158
    r8: 0x000000000000000a   r9: 0x0000000000000011  r10: 
0x0000000000000000  r11: 0x0000000000000206
   r12: 0x0000000000000307  r13: 0x00007ffeec87b3c6  r14: 
0x0000000000000006  r15: 0x000000000000002d
   rip: 0x00007fff4fe8cb66  rfl: 0x0000000000000206  cr2: 0x000000010343d088

Logical CPU:     6
Error Code:      0x00000004
Trap Number:     14

-- 
/Jacob Carlborg