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

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

Notice (2018-05-24): bugzilla.xamarin.com is now in read-only mode.

Please join us on Visual Studio Developer Community and in the Xamarin and Mono organizations on GitHub to continue tracking issues. Bugzilla will remain available for reference in read-only mode. We will continue to work on open Bugzilla bugs, copy them to the new locations as needed for follow-up, and add the new items under Related Links.

Our sincere thanks to everyone who has contributed on this bug tracker over the years. Thanks also for your understanding as we make these adjustments and improvements for the future.


Please create a new report on GitHub or Developer Community with your current version information, steps to reproduce, and relevant error messages or log files if you are hitting an issue that looks similar to this resolved bug and you do not yet see a matching new report.

Related Links:
Status:
RESOLVED INVALID

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.