0

which one is best method to find out the solution of this type of crash or other suggestion to understand and solve the crash?

app crash on iphone 4s(iOS7),iphone5(iOS7), and iphone5s(iOS7) devices and work fine in all other devices(iOS8) as well

get EXC_BAD_ACCESS error in main fucntion.

on iphone4s -> exc_BAD_Access(Code=1,address=0xe000000c)

on iphone5 -> EXC_BAD_ACCESS(code=1,address=0x8955f985)

on iphone5s -> exc_bad_access(code=exc_i386_gpflt)

i am not able to find out crash point, crash report is given below

using zombies get EXC_BREAKPOINT(code=EXC_I386_BPT, subcode0x0) on thread1 0 _ _ forwarding _ _

2015-09-07 18:20:36.412 Application[2248:607] *** -[ViewController retain]: message sent to deallocated instance 0x7e6a2a30

Incident Identifier: A1583491-E436-49A4-967A-6DB2BE55ED9B
CrashReporter Key:   d0fc48d1d5f4d462334236dabac50669f2b9d217
Hardware Model:      iPhone3,1
Process:         Application [1691]
Path:            (null)
Identifier:      com.XXX.XX
Version:         1.2 (1.0)
Code Type:       ARM
Parent Process:  launchd [1]

Date/Time:       2015-09-03 17:36:38.000 +0530
OS Version:      iPhone OS 7.1.2 (11D257)
Report Version:  104

Exception Type:  EXC_BAD_ACCESS (SIGSEGV)
Exception Codes: KERN_INVALID_ADDRESS at 0xb000000c
Crashed Thread:  0

Thread 0 Crashed:
  0   libobjc.A.dylib                 0x3af6a626 0x3af5d000 + 54822      (objc_msgSend + 6)
  1   UIKit                           0x3307b5b0 0x32fc2000 + 759216 (<redacted> + 1324)
  2   UIKit                           0x3307adf8 0x32fc2000 + 757240 (<redacted> + 568)
  3   UIKit                           0x3307ab68 0x32fc2000 + 756584 (<redacted> + 40)
  4   UIKit                           0x3307ab00 0x32fc2000 + 756480 (<redacted> + 180)
  5   UIKit                           0x03049ab0 0x2ff8000 + 334512 (-[UILayoutContainerViewAccessibility(SafeCategory) layoutSubviews] + 40)
  6   UIKit                           0x32fccd58 0x32fc2000 + 44376 (<redacted> + 380)
  7   QuartzCore                      0x32c4a628 0x32c3e000 + 50728 (<redacted> + 140)
     .
     .
     .

  Thread 1:
  0   libsystem_kernel.dylib          0x3b510808 0x3b510000 + 2056 (kevent64 + 24)
  1   libdispatch.dylib               0x3b44bf70 0x3b447000 + 20336 (<redacted> + 36)

 Thread 2:
 0   libsystem_kernel.dylib          0x3b510a58 0x3b510000 + 2648 (mach_msg_trap + 20)
 1   libsystem_kernel.dylib          0x3b513ef8 0x3b510000 + 16120 (thread_suspend + 44)
 2   Application                     0x0027a3f0 0x7b000 + 2094064 (ksmachexc_i_handleExceptions + 128)
 3   libsystem_pthread.dylib         0x3b58c918 0x3b58a000 + 10520 (<redacted> + 140)
 4   libsystem_pthread.dylib         0x3b58c888 0x3b58a000 + 10376 (_pthread_start + 100)

 Thread 3:

 Thread 4:
  0   libsystem_kernel.dylib          0x3b510a58 0x3b510000 + 2648 (mach_msg_trap + 20)
  1   CoreFoundation                  0x3077a848 0x306dc000 + 649288 

 Thread 5:
  0   libsystem_kernel.dylib          0x3b523434 0x3b510000 + 78900 (select$DARWIN_EXTSN + 20)
  1   libsystem_pthread.dylib         0x3b58c918 0x3b58a000 + 10520 (<redacted> + 140)
  2   libsystem_pthread.dylib         0x3b58c888 0x3b58a000 + 10376 (_pthread_start + 100)

 Thread 6:
  0   libsystem_kernel.dylib          0x3b510a58 0x3b510000 + 2648 (mach_msg_trap + 20)
  1   CoreFoundation                  0x3077a848 0x306dc000 + 649288 (<redacted> + 152)
  2   CoreFoundation                  0x30778f70 0x306dc000 + 642928 (<redacted> + 784)


 Thread 7:
  0   libsystem_kernel.dylib          0x3b510a58 0x3b510000 + 2648 (mach_msg_trap + 20)
  1   CoreFoundation                  0x3077a848 0x306dc000 + 649288 (<redacted> + 152)
  2   CoreFoundation                  0x30778f70 0x306dc000 + 642928 (<redacted> + 784)
  3   CoreFoundation                  0x306e3eb8 0x306dc000 + 32440 (CFRunLoopRunSpecific + 516)


Thread 8:
 0   libsystem_kernel.dylib          0x3b510a58 0x3b510000 + 2648 (mach_msg_trap + 20)
 1   CoreFoundation                  0x3077a848 0x306dc000 + 649288 (<redacted> + 152)


 Thread 9:
   0   libsystem_kernel.dylib          0x3b523c70 0x3b510000 + 81008 (__workq_kernreturn + 8)

  Thread 10:
 0   libsystem_kernel.dylib          0x3b523c70 0x3b510000 + 81008 (__workq_kernreturn + 8)

 Thread 11:
 0   libsystem_kernel.dylib          0x3b523c70 0x3b510000 + 81008 (__workq_kernreturn + 8)

 Thread 12:
  0   libsystem_kernel.dylib          0x3b523c70 0x3b510000 + 81008 (__workq_kernreturn + 8)

Thread 0 crashed with ARM Thread State:
   r0: 0x187474c0     r1: 0x335f927d     r2: 0x3b73cf78     r3: 0x00000003 
   r4: 0x1a80c750     r5: 0x33624ba7     r6: 0x3bbc2b00     r7: 0x2 7d86a34 
   r8: 0x187474c0     r9: 0xb0000000    r10: 0x180a06a0    r11: 0x180a06a0 
   ip: 0x3b714740     sp: 0x27d86a04     lr: 0x306eb675     pc: 0x3af6a626 
  cpsr: 0x70000030 

Binary Images:
     0x7b000 -   0x7c6fff  Application armv7  <07bdf31176343598ba6467dab231106a> /var/mobile/Applications/80D6634E-C9E7-4B34-B42D-6E208E4D878A/Application.app/Application
 0x2fd67000 - 0x2fdcefff  AddressBook armv7  <c742d15daada36238f237d74bcfb7f0e>......

 Extra Information:

  Stack Dump (0x27d869dc-0x27d86a54):

  006C4817986C481750C7801A00000000000000002020401050C7801AA74B6233346AD82775B66E30A0060A18C07474184069D41650C7801A0100000021B36E30006C4817A0060A18A0060A1850C7801AA74B623380B3E0164C6BD827B3B50733000000000000A0430000F04300000000000080420000A043

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        "_savedNavBarStyleBeforeSheet": 0,
        "_statusBarHeightForHideShow": 0,
        "_toolbar": {
            "address": 0,
            "type": "null_pointer"
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    },
    "type": "objc_object"
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"stack@0x27d86a28": {
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    "class": "__NSDictionaryM",
    "ivars": {
        "_mutations": 2,
        "_size": 3
    },
    "type": "objc_object"
},
"stack@0x27d86a2c": {
    "address": 862079911,
    "type": "string",
    "value": "navigationController:willShowViewController:animated:"
},
"stack@0x27d86a30": {
    "address": 383824768,
    "class": "UIViewControllerWrapperView",
    "ivars": {
        "_tightWrappingDisabled": 1
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    "type": "objc_object"
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  }

Application Stats:
 {
"active_time_since_last_crash": 267.14,
"active_time_since_launch": 267.14,
"application_active": true,
"application_in_foreground": true,
"background_time_since_last_crash": 44.8144,
"background_time_since_launch": 44.8144,
"launches_since_last_crash": 1,
"sessions_since_last_crash": 3,
"sessions_since_launch": 3
  }

 CrashDoctor Diagnosis: Attempted to dereference garbage pointer 0xb000000c.

can anybody suggests me to solve this type of crash or way to detect the problem or crash point where app get crash

Test At
  • 58
  • 2
  • 11
  • possible duplicate of [iOS App crash with SIGTRAP in iPhone 6 plus?](http://stackoverflow.com/questions/32002814/ios-app-crash-with-sigtrap-in-iphone-6-plus) – Anbu.Karthik Sep 07 '15 at 10:53
  • app crash on only in iOS 7 devices – Test At Sep 07 '15 at 10:55
  • is not crash , it is the exception , the bus type does not identify the particular error , so the link may be helps with you – Anbu.Karthik Sep 07 '15 at 10:56
  • You can add a exception breakpoint to find the crash point. – mengxiangjian Sep 07 '15 at 11:00
  • what is your build target ? – Jan ATAC Sep 07 '15 at 11:02
  • build target -> 7.0 @CanATAC – Test At Sep 07 '15 at 11:10
  • where can i add exception breakpoint? @mengxiangjian – Test At Sep 07 '15 at 11:10
  • objc_msgSend is most often a result of sending a message to a deallocated object. (Less often a message to the wrong type of object.). Try running with zombies enabled to see what object is causing the problem. – Phillip Mills Sep 07 '15 at 12:43
  • using zombies get EXC_BREAKPOINT(code=EXC_I386_BPTmsubcode0x0) on thread1 0 _ _ _forwarding_ _ _ 2015-09-07 18:20:36.412 Application[2248:607] *** -[MMMFriendListVC retain]: message sent to deallocated instance 0x7e6a2a30 @PhillipMills – Test At Sep 07 '15 at 12:56
  • OK, so how are you using that controller? Is it a delegate/datasource for anything? What is supposed to keep it in memory? – Phillip Mills Sep 07 '15 at 13:50
  • this view controller[MMMFriendListVC] have UItableview (UITableViewDataSource,UITableViewDelegate)@PhillipMills – Test At Sep 07 '15 at 13:57
  • In Xcode, press (command + 7). Add breakpoint via "+" at bottom. – mengxiangjian Sep 08 '15 at 05:20
  • i already done it but it doesnt genrate exception @mengxiangjian – Test At Sep 08 '15 at 05:27
  • when i enable zombies then i get EXC_BREAKPOINT(code=EXC_I386_BPTmsubcode0x0) on thread1 0 _ _ forwarding _ _ 2015-09-07 18:20:36.412 Application[2248:607] *** -[MMMFriendListVC retain]: message sent to deallocated instance 0x7e6a2a30 @mengxiangjian – Test At Sep 08 '15 at 05:28
  • When you send message to an instance, make sure the instance is alive.So you can use `if (someInstance) { [someInstance method] }` to avoid this problem. – mengxiangjian Sep 08 '15 at 05:42
  • i am using setter to assign value as like [[AppCommonFunctions sharedInstance]pushVCOfClass:[MMMFriendListVC class] fromNC:[self navigationController] animated:NO popFirstToVCOfClass:nil modifyVC:^(id info) { [((MMMFriendListVC *)info)setEventId:[people objectForKey:@"id"]]; [((MMMFriendListVC *)info)setFriednListArr:friednListArr]; [((MMMFriendListVC *)info)setSendDic:sendDic]; [self dismissViewControllerAnimated:false completion:nil]; }]; @mengxiangjian – Test At Sep 08 '15 at 06:03

1 Answers1

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Seems like issue with memory management and maybe with (accessibilityUILayoutContainerViewAccessibility in log). It can be possible to detect unexpected deallocation of MMMFriendListVC by adding breakpoint to method

- (void)dealloc{}

in MMMFriendListVC. If you are using ARC it is still possible to use this method with just single NSLog inside. With ARC, make sure to avoid storing NSObject subclasses in properties of type assign because they won't be nullified after deallocation - making possible calling deallocated variable. Without ARC make sure to set pointer as nil after releasing it.

If Voice Over was active at the moment of crash it can explain difference between iOS 7 and iOS 8, because VO is having surprising differences in implementation on different iOS version. Sometimes it can be necessary to store retained pointer to view controller a bit longer than expected (for example in NSDictionary for at least some more seconds) to make sure that object won't get called. Maybe in iOS 7 view controller was stored by system as delegate represented by assigned pointer... It is also possible that iOS 7 is a bit faster with deallocating variable with zero retains, and that also would explain observed difference in behaviour.

For this moment I suppose one of this possibilities is cause of crash.

Adam Tucholski
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