Is this definitely a memory crash, or should I be looking for something else?
Exception Type: EXC_BAD_ACCESS (SIGSEGV)
Exception Codes: KERN_INVALID_ADDRESS at 0x81093cd0
Crashed Thread: 0
Thread 0 name: Dispatch queue: com.apple.main-thread
Thread 0 Crashed:
0 libobjc.A.dylib 0x33563f78 objc_msgSend + 16
1 Foundation 0x34d6b92c __NSFireDelayedPerform + 408
2 CoreFoundation 0x35919a2c __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ + 8
3 CoreFoundation 0x35919692 __CFRunLoopDoTimer + 358
4 CoreFoundation 0x35918268 __CFRunLoopRun + 1200
5 CoreFoundation 0x3589b49e CFRunLoopRunSpecific + 294
6 CoreFoundation 0x3589b366 CFRunLoopRunInMode + 98
7 GraphicsServices 0x33636432 GSEventRunModal + 130
8 UIKit 0x33073cce UIApplicationMain + 1074
Using the profiler, live bytes are well under 10MB at all times, and when memory warns happen I'm back to 3MB or below.
This statement returns YES, so I assume I have zombies enabled:
getenv("NSZombieEnabled") || getenv("NSAutoreleaseFreedObjectCheckEnabled")
When I'm running from Xcode, the app crashes without Xcode even being aware (after some arbitrary number of memory warns).
Any suggestions besides "run with NSZombies enabled?" And, is this definitely a memory crash?
SIGSEGV happens when the code tries to access memory that "doesn't exist" (that is, the address you are trying to use doesn't have a mapping in your virtual address space).
The exact cause of this can be a large number of things - the most common ones are:
Using pointers that are not (properly) initialized.
Walking off the end of an array.
Using memory that has been freed.
Note that all of the above are examples of "undefined behaviour", so you may well have situations where your code doesn't crash although it's doing something wrong, but the same code, under other circumstances, DOES go wrong.
Yes, this is a memory-related error (segmentation fault). Keep in mind that NSZombies can't catch every memory error.
Related
I experiencing a crash in my app:
Thread 0 name:
Thread 0 Crashed:
0 LogoQuizAC 0x0000000104705218 __hidden#563_ + 0 (__hidden#957_:0)
1 LogoQuizAC 0x0000000104705218 _hidden#18_ + 592 (__hidden#957_:135)
2 LogoQuizAC 0x000000010470503c __hidden#564_ + 48 (__hidden#456_:0)
3 LogoQuizAC 0x000000010470503c _hidden#18_ + 116 (__hidden#957_:135)
4 LogoQuizAC 0x00000001046fcd6c _hidden#17_ + 504 (__hidden#454_:96)
5 LogoQuizAC 0x00000001046fcea0 _hidden#20_ + 36 (__hidden#456_:0)
6 Foundation 0x0000000182770b20 __NSFireTimer + 68 (NSTimer.m:270)
7 CoreFoundation 0x0000000181355fa0 __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ + 32 (CFRunLoop.c:1807)
8 CoreFoundation 0x0000000181355ba0 __CFRunLoopDoTimer + 1064 (CFRunLoop.c:2415)
9 CoreFoundation 0x0000000181354ffc __CFRunLoopDoTimers + 328 (CFRunLoop.c:2575)
10 CoreFoundation 0x000000018134eee4 __CFRunLoopRun + 1936 (CFRunLoop.c:3090)
11 CoreFoundation 0x000000018134e21c CFRunLoopRunSpecific + 600 (CFRunLoop.c:3242)
12 GraphicsServices 0x0000000198f18784 GSEventRunModal + 164 (GSEvent.c:2259)
13 UIKitCore 0x0000000183d8eee8 -[UIApplication _run] + 1072 (UIApplication.m:3253)
14 UIKitCore 0x0000000183d9475c UIApplicationMain + 168 (UIApplication.m:4707)
15 LogoQuizAC 0x000000010453a404 main + 68 (RLockedCell.swift:21)
16 libdyld.dylib 0x000000018100e6b0 start + 4
I tried almost everything but can symbolicate the crash.
I tried using symbolicatecrash followed by these posts:
(_hidden#919_:0) inside crash symbolication file
Why aren't the crashlogs from Testflight symbolicating in Xcode?
Xcode Crash Organizer does Not Symbolicate .xccrashpoint Files
How to symbolicate crash log with Xcode 8?
how Symbolicate a crash file using xcarchive
How to symbolicate crash log Xcode?
But without any success.
What am I doing wrong? How can I figure out what causing the crash?
The good news that it is crashing in your code, not in Operating Systems or Library code, so you have a good chance to debug it. Your code that is crashing is running off a timer. Sometimes these bugs are seen because in testing, you are just testing the app. But in the real world, those timers fire when you are not expecting them.
For example, someone ran your app, then put it into the background when using another app, or for example they received a phone call whilst using the app. If you attach the full contents of the .crash file, it will give more information on the cause of the crash.
Another thing you can do is place asserts into your code, such as in your timer callback functions for each object you are relying on being non-null.
You may find that your app is trying to draw onto the screen but is in the background. This is a common reason for a crash seen in the field for games that use timers. That may sound like a generalisation but it is a suggestion to try and make you think differently about the real world environment your customers face which can the reason for the failure.
I'm getting a crash periodically with a gpus_ReturnGuiltyForHardwareRestart.
The crash is sporadic, and occurs in a complex multi-threaded app. Sample stack trace below.
It seems to occur (which is rare) when the UI and related handlers are being stressed (think hyperactive user making lots of gestures as quickly as the app and system will allow), with lots of resulting calls to behind-the-scenes and up-front rendering.
Researching gpus_ReturnGuiltyForHardwareRestart suggests this may be due to a buffer issue, e.g. a buffer overrun due to an incorect binding or failure to unbind.
gpus_ReturnGuiltyForHardwareRestart crash
(not relevant, but I did look: gpus_ReturnGuiltyForHardwareRestart)
My understanding is that a buffer gets corrupted in some way, and the crash happens sometime later when the corrupted buffer is accessed.
I've been through the code and made sure every bound buffer and texture is subsequently unbound to prevent unwanted/unintentional changes by later code; still getting the crash.
I did just come across these, suggesting the possibility of a bug in the OS:
iOS 9 Beta 4 crash: gpus_ReturnGuiltyForHardwareRestart (original poster indicated was fixed in 9 beta 5)
Re: OpenGLES driver crash in iOS9 Beta2/3
However, I'm currently testing on 9.3.4, so it seems this would be fixed.I've tried making sure all buffers are properly unbound after use, and tried periodic use of glFlush(), both without success.
Does anybody have experience with this, any knowledge on potential sources, means of tracking down causes, or fixes?
Stack trace:
Date/Time: 2016-08-11T20:20:40Z
Launch Time: 2016-08-11T20:15:22Z
OS Version: iPhone OS 9.3.4 (13G35)
Report Version: 104
Exception Type: SIGSEGV
Exception Codes: SEGV_ACCERR at 0x1
Crashed Thread: 0
Thread 0 Crashed:
0 libGPUSupportMercury.dylib 0x0000000191bd9f28 gpus_ReturnGuiltyForHardwareRestart + 12
1 libGPUSupportMercury.dylib 0x0000000191bdaec4 gpusSubmitDataBuffers + 168
2 GLEngine 0x0000000195e9f1e4 gliPresentViewES_Exec + 172
3 GLEngine 0x0000000195e9f0fc gliPresentViewES + 80
4 OpenGLES 0x000000018576bc44 -[EAGLContext presentRenderbuffer:] + 68
5 NWFPApp 0x00000001001ef8fc -[NWFPIOSGLView renderNormalBuffers] (NWFPIOSGLView.mm:543)
6 NWFPApp 0x00000001001ef814 -[NWFPIOSGLView renderAll] (NWFPIOSGLView.mm:516)
7 NWFPApp 0x00000001001ee780 -[NWFPIOSGLView doInContext:] (NWFPIOSGLView.mm:135)
8 NWFPApp 0x00000001001ef770 -[NWFPIOSGLView drawView] (NWFPIOSGLView.mm:494)
9 NWFPApp 0x0000000100203cc8 -[NWFPGLChoreographer displayLinkEvent:] (NWFPGLChoreographer.m:128)
10 QuartzCore 0x000000018614022c CA::Display::DisplayLinkItem::dispatch() + 36
11 QuartzCore 0x00000001861400e0 CA::Display::DisplayLink::dispatch_items(unsigned long long, unsigned long long, unsigned long long) + 420
12 IOKit 0x0000000183885e54 IODispatchCalloutFromCFMessage + 368
13 CoreFoundation 0x00000001835ad030 __CFMachPortPerform + 176
14 CoreFoundation 0x00000001835c57d4 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 52
15 CoreFoundation 0x00000001835c4f0c __CFRunLoopDoSource1 + 432
16 CoreFoundation 0x00000001835c2c64 __CFRunLoopRun + 1796
17 CoreFoundation 0x00000001834ecc50 CFRunLoopRunSpecific + 380
18 GraphicsServices 0x0000000184dd4088 GSEventRunModal + 176
19 UIKit 0x00000001887ce088 UIApplicationMain + 200
20 NWFPApp 0x00000001002af1a0 main (main.m:30)
21 ??? 0x000000018308a8b8 0x0 + 0
I have a problem with my iOS app crashing. It uses core data (one managed object context) and ARC but also has a separate SQLite database, which can be fairly large. I am getting crash reports for it with the error: EXC_BAD_ACCESS and usually with the code: KERN_INVALID_ADDRESS
The problem is that every single crash happens in a different place (there are over 30) and that usually those places don't usually include any of my code in the call stack. I think, therefore that I am doing something fundamentally wrong which is causing these errors to occur.
I have tried turning on NSZombiesEnabled, but then I find that the errors don't occur. Also, I have tried turning on core data debugging (level 1), but I find the same there too. The errors occur across a range of devices and operating systems. The crash reports show between 3.0 to 148.0 mb or ram remaining. All of the crashes are on the main thread.
So my question comes in two parts:
1) I can't find any reference to there being a problem using a separate SQLLite database in a core data project. Is there any potential pitfalls to doing this and docs on how to avoid those pitfalls?
2) Does this patten of errors suggest anything in particular which I may be doing incorrectly?
I have added a single crash report on the off chance it reveals something which my question does not:
0
com.apple.main-thread Crashed
0 CoreFoundation CFRetain + 19
1 CoreFoundation __CFRunLoopDoTimer + 690
2 CoreFoundation __CFRunLoopDoTimer + 690
3 CoreFoundation __CFRunLoopRun + 1232
4 CoreFoundation CFRunLoopRunSpecific + 356
5 CoreFoundation CFRunLoopRunInMode + 104
6 GraphicsServices GSEventRunModal + 74
7 UIKit UIApplicationMain + 1120
8 cleverme
main.m line 14
main
I am using Bugsense in my app to get crash reports.
I have a repeating bug with SIGSEGV and no other details about it.
I tried to symbolicate the report but I get this:
0 libobjc.A.dylib 0x33417f78 0x33414000 + 16248
1 CoreFoundation 0x36f651fb 0x36f4d000 + 98811
2 Foundation 0x32c42747 0x32b9e000 + 673607
3 CoreFoundation 0x36fdaad3 0x36f4d000 + 580307
4 CoreFoundation 0x36fda29f 0x36f4d000 + 578207
5 CoreFoundation 0x36fd9045 0x36f4d000 + 573509
6 CoreFoundation 0x36f5c4a5 CFRunLoopRunSpecific + 300
7 CoreFoundation 0x36f5c36d CFRunLoopRunInMode + 104
8 GraphicsServices 0x35123439 GSEventRunModal + 136
9 UIKit 0x35205cd5 UIApplicationMain + 1080
10 English Club 0x00036a2b 0x34000 + 10795
It does not point to any of my classes (In the last line 'English Club' is the name of my app).
Does that mean that this is a bug in apple classes? how can I parse this report to get somthing helpful (like what are the +1234334 numbers in this case etc.
Thank you all
Shani
Does that mean that this is a bug in apple classes?
No.
how can I parse this report to get somthing helpful
Recompile with debug symbols enabled, and run the app in the debugger. Then, if everything was done right, you'll get a symbolicated stack trace.
what are the +1234334 numbers in this case
They're offsets from the beginning of the particular function address - and you're most likely not interested in them.
Your best bet here is to enable zombies and rerun in the debugger and try to reproduce the crash manually. The bug is likely somwhere in your code where you set a delegate that points to one of your objective C objects. For example, see this question which is much like yours: SIGSEGV SEGV_ACCERR Crash Reports - What to do?
An iPhone app is crashing on the device but not on the simulator. So I'm trying to learn how to interpret the crash log. I read lots of forum posts saying that the symbolicated crash log shows a back trace that gives the method and line number of the calls leading to the crash but I don't see anything useful. Maybe I'm not looking at the symbolicated crash log. Here is the beginning of what I see:
Incident Identifier: 432A8974-1661-409F-B5A6-970148550A46
CrashReporter Key: db93147c0a70a5f4c60dc92f826e72d5a74477c8
Hardware Model: iPhone3,3
Process: Darken [57959]
Path: /var/mobile/Applications/CB27C10F-CD3B-4148-8321-2C251888B27B/Darken.app/Darken
Identifier: Darken
Version: ??? (???)
Code Type: ARM (Native)
Parent Process: launchd [1]
Date/Time: 2012-02-25 10:43:47.753 -0500
OS Version: iPhone OS 4.2.10 (8E600)
Report Version: 104
Exception Type: EXC_BAD_ACCESS (SIGBUS)
Exception Codes: KERN_PROTECTION_FAILURE at 0x00000008
Crashed Thread: 0
Thread 0 Crashed:
0 libobjc.A.dylib 0x32716464 objc_msgSend + 16
1 UIKit 0x3245e6fe -[UIScrollView(UIScrollViewInternal) _scrollViewAnimationEnded] + 90
2 CoreFoundation 0x32071bb8 -[NSObject(NSObject) performSelector:withObject:] + 16
3 UIKit 0x3245e5b8 -[UIAnimator stopAnimation:] + 276
4 UIKit 0x323efbf2 -[UIAnimator(Static) _advance:] + 214
5 UIKit 0x323efb0e LCDHeartbeatCallback + 10
6 GraphicsServices 0x35474362 HeartbeatVBLCallback + 86
7 IOMobileFramebuffer 0x34739bf4 IOMobileFramebufferVsyncNotifyFunc + 68
8 IOKit 0x348e5e64 IODispatchCalloutFromCFMessage + 192
9 CoreFoundation 0x32070be0 __CFMachPortPerform + 204
10 CoreFoundation 0x320686f8 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 20
11 CoreFoundation 0x320686bc __CFRunLoopDoSource1 + 160
12 CoreFoundation 0x3205af76 __CFRunLoopRun + 514
13 CoreFoundation 0x3205ac80 CFRunLoopRunSpecific + 224
14 CoreFoundation 0x3205ab88 CFRunLoopRunInMode + 52
15 GraphicsServices 0x354724a4 GSEventRunModal + 108
16 GraphicsServices 0x35472550 GSEventRun + 56
17 UIKit 0x323c7d1a -[UIApplication _run] + 406
18 UIKit 0x323c5884 UIApplicationMain + 664
19 Darken 0x000029d6 0x1000 + 6614
20 Darken 0x00002998 0x1000 + 6552
... Threads other than 0 listed here
Is anything here useful for finding out which line of my code led to the crash? Darken is the name of the application -- I already knew that. The only method name I recognize is UIApplicationMain but the crash didn't happen when the app was first launched -- I was running it about a minute and doing dozens of functions before the crash.
You may want to try and set NSZombieEnabled to YES in your project and let it crash with your device running in debug. It should stop at the line of code causing your crash. Your error looks like it is an EXC_BAD_ACCESS which usually means you were trying to access some deallocated memory.
You won't get a line number from a crash dump (unless you compiled your app with -g and run in GDB, but I doubt it since you don't seem to know what these are at all).
You ARE looking at the symbolicated crash dump: you DO have the names of the functions in the call stack. The crash occurs in the last called (topmost) function, which is objc_msgSend. That means you're not properly balancing your alloc/retain/copy methods with autorelease/release, and the messenger function tries to access already freed/corrupted/nonexistent memory, hence the crash (EXC_BAD_ACCESS is similar to a segfault, in fact you'll get one of these when you make such a mistake).
So my advice is, triple check your code for method calls modifying the reference count.