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There's a crash which happened only once so far with no obvious reasons. We are planning to upgrade to 5.2 but we'd like to make sure it'll fix the crash.
the codeline where it happens is:
UIView containerView = new UIView ();
MonoTouch is 5.1.1
The crash dump is below (sensitive info is removed).
Incident Identifier: 9920E0D6-7D2E-455E-A4C3-8F4A313D98AA
CrashReporter Key: b352a20df7ca6ca0c0cd56d04b0c66116d598428
Hardware Model: iPhone3,1
Version: ??? (???)
Code Type: ARM (Native)
Parent Process: launchd 
Date/Time: 2012-02-23 11:31:04.301 +0000
OS Version: iPhone OS 5.0 (9A334)
Report Version: 104
Exception Type: EXC_BAD_ACCESS (SIGABRT)
Exception Codes: KERN_INVALID_ADDRESS at 0x00000000
Crashed Thread: 0
Thread 0 name: Dispatch queue: com.apple.main-thread
Thread 0 Crashed:
0 libsystem_kernel.dylib 0x31fa432c __pthread_kill + 8
1 libsystem_c.dylib 0x3649af54 pthread_kill + 48
2 libsystem_c.dylib 0x36493fe4 abort + 88
3 App 0x007e63de mono_handle_native_sigsegv (mini-exceptions.c:2250)
4 App 0x007d2a7a mono_sigsegv_signal_handler (mini.c:5921)
5 libsystem_c.dylib 0x364a5532 _sigtramp + 42
6 libsystem_c.dylib 0x36458dbe pthread_mutex_trylock + 262
7 App 0x0088f694 GC_register_finalizer_no_order (finalize.c:498)
8 App 0x0081d69a object_register_finalizer (gc.c:303)
9 App 0x0081d7b0 mono_object_register_finalizer (gc.c:324)
10 App 0x0084e238 mono_object_new_alloc_specific (object.c:4336)
11 App 0x0084e388 mono_object_new_specific (object.c:4319)
12 App 0x00447a4c wrapper_managed_to_native_object___icall_wrapper_mono_object_new_specific_intptr (mscorlib.dll.7.s:541187)
13 App 0x006eefa4 monotouch_MonoTouch_Foundation_NSObject_InitializeObject_bool (monotouch.dll.7.s:24520)
14 App 0x006eed44 monotouch_MonoTouch_Foundation_NSObject__ctor_MonoTouch_Foundation_NSObjectFlag (monotouch.dll.7.s:24274)
15 App 0x006ff3f4 monotouch_MonoTouch_UIKit_UIResponder__ctor_MonoTouch_Foundation_NSObjectFlag (monotouch.dll.7.s:48743)
16 App 0x00705f0c monotouch_MonoTouch_UIKit_UIView__ctor (monotouch.dll.7.s:59386)
I've been running a memory torture test lately (creating tons of NSObject derived objects) and I have not seen a similar crashes. Of course if this occurs when running out of memory it might be hard (or even impossible) to duplicate the exact same crash.
If you can share (mark it private) the full stack trace, crash dump and your build options we can try to duplicate it with the latest code (i.e. what's being QA'ed right now).
Also there were a lot of (other) fixes done between the early 5.1 (beta) days and the latest 5.2.5 (stable) release that would make your upgrade worthwhile.
It doesn't seem to be a memory issue there is no memory warnings and other processes aren't being killed.
the build settings we use are the following (only trimmed 3rd party libs):
"MtouchExtraArgs" = "-aot \"nimt-trampolines=2048\" -gcc_flags '-lgcc_eh"
"DefineConstants" = "MONOTOUCH;PRODUCTION;"
"Optimize" = "true"
"MtouchUseLlvm" = "true"
"MtouchArch" = "ARMv6_ARMv7"
"MtouchUseThumb" = "false"
Does it still happen if you create a new project from a template and do "UIView containerView = new UIView ();" there? If not, it's likely an issue with your project, and we'd probably need to access it to find out what's going on.
This crash happened only once in testing and is not reproducible. Creating new project will not give us a definitive result since it may not crash until went into production. We are going to upgrade to 5.2 and hopefully GC fixes if there are any will fix this issue.
I'll also let you know if something like this happens again.
Thanks for looking into it. It definitely helps that you don't see issues like this often.
I will close this since it's not reproducible: if you find a way to reproduce it, please reopen the bug report and we'll have another look at it.