Bug 15095 - Crashes when running on multiple threads
Summary: Crashes when running on multiple threads
Alias: None
Product: Runtime
Classification: Mono
Component: General ()
Version: 3.2.x
Hardware: Other Other
: --- normal
Target Milestone: ---
Assignee: Bugzilla
Depends on:
Reported: 2013-10-01 10:01 UTC by Chris Leow
Modified: 2013-10-01 16:34 UTC (History)
3 users (show)

Is this bug a regression?: ---
Last known good build:

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Description Chris Leow 2013-10-01 10:01:05 UTC
Running a Xamarin app on the latest Xamarin.iOS (v7.0) on iPad mini, the app occasionally crashes with the following crash report from testflight (after the .dSYM was added):

#	Binary Image Name	Address	Symbol
0	BlastOutAppUITouch	0x0002d712	testflight_backtrace
1	BlastOutAppUITouch	0x0002e360	TFSignalHandler
2	libsystem_platform.dylib	0x3b1e0062	_sigtramp
3	BlastOutAppUITouch	0x016b206c	 in threads.c on Line 1428
4	BlastOutAppUITouch	0x016b1a04	start_wrapper in threads.c on Line 608
5	BlastOutAppUITouch	0x016c8ea2	thread_start_routine in wthreads.c on Line 294
6	BlastOutAppUITouch	0x016d0f90	inner_start_thread in mono-threads-posix.c on Line 49
7	BlastOutAppUITouch	0x016e618a	GC_start_routine in pthread_support.c on Line 1526
8	libsystem_pthread.dylib	0x3b1e4c1c	_pthread_body
9	libsystem_pthread.dylib	0x3b1e4b8e	_pthread_start
10	libsystem_pthread.dylib	0x3b1e2c8f	thread_start

Seems to be too low level for my app-code to be at fault...  Not sure what else I can provide to shed light on this issue.
Comment 1 Rolf Bjarne Kvinge [MSFT] 2013-10-01 10:06:57 UTC
This may be a NullRefenceException confusing TestFlight - this is explained (with a fix) here: http://stackoverflow.com/questions/14499334/how-to-prevent-ios-crash-reporters-from-crashing-monotouch-apps ?

If that's not the case please attach a complete crash report (it's also important to know what the other threads are doing).
Comment 2 Chris Leow 2013-10-01 11:19:28 UTC
We got this crash log from TestFlight, so that's probably it in this case!

Thanks for the incredibly rapid response!  I shall expect virtual telepathy from Xamarin tech support in the near future ;)
Comment 3 Rolf Bjarne Kvinge [MSFT] 2013-10-01 16:34:22 UTC
I'm closing this then, please reopen if you can still reproduce after implementing the fix from comment #2.