Unable to read the crash log

Question

I have an app which is working fine on devices & simulators.

However it is rejected saying crash report as below.

Incident Identifier: 2FB27688-F4D3-4732-9F25-3236842E257B
CrashReporter Key:   61eca33f3648a28cbd5c7ef93baf84b507e50ae0
Hardware Model:      xxx
Process:             xxxxxx [6947]
Path:                /private/var/mobile/Containers/Bundle/Application/9F859536-E359-41FC-B3CA-398683B8E19F/xxxxxx.app/xxxxxx
Identifier:          com.xxxxxx.app
Version:             1.5.4.1 (1.5.4)
Code Type:           ARM-64 (Native)
Parent Process:      launchd [1]

Date/Time:           2015-11-19 14:05:23.23 -0800
Launch Time:         2015-11-19 14:05:23.23 -0800
OS Version:          iOS 9.1 (13B143)
Report Version:      105

Exception Type:  EXC_CRASH (SIGABRT)
Exception Codes: 0x0000000000000000, 0x0000000000000000
Exception Note:  EXC_CORPSE_NOTIFY
Triggered by Thread:  0

Filtered syslog:
None found

Last Exception Backtrace:
(0x1824f8f48 0x19733ff80 0x1824f8e90 0x18336f4ec 0x1000c9828 0x187b01324 0x187d2facc 0x187d33e0c 0x187d30f50 0x18c16f7c4 0x18c16fb44 0x1824b0544 0x1824affd8 0x1824adcd8 0x1823dcca0 0x187afa1c8 0x187af4ffc 0x10011a09c 0x197b8e8b8)

Thread 0 name:  Dispatch queue: com.apple.main-thread
Thread 0 Crashed:
0   libsystem_kernel.dylib          0x0000000197cab140 0x197c90000 + 110912
1   libsystem_pthread.dylib         0x0000000197d74ef8 0x197d70000 + 20216
2   libsystem_c.dylib               0x0000000197c1eb78 0x197bbc000 + 404344
3   libc++abi.dylib                 0x00000001969b53f4 0x1969b4000 + 5108
4   libc++abi.dylib                 0x00000001969d1e98 0x1969b4000 + 122520
5   libobjc.A.dylib                 0x0000000197340248 0x197338000 + 33352
6   libc++abi.dylib                 0x00000001969cef44 0x1969b4000 + 110404
7   libc++abi.dylib                 0x00000001969ceb10 0x1969b4000 + 109328
8   libobjc.A.dylib                 0x0000000197340120 0x197338000 + 33056
9   CoreFoundation                  0x00000001823dcd48 0x1823d4000 + 36168
10  UIKit                           0x0000000187afa1c8 0x187a74000 + 549320
11  UIKit                           0x0000000187af4ffc 0x187a74000 + 528380
12  xxxxxx                      0x000000010011a09c 0x1000bc000 + 385180
13  libdyld.dylib                   0x0000000197b8e8b8 0x197b8c000 + 10424

Thread 1 name:  Dispatch queue: com.apple.libdispatch-manager
Thread 1:
0   libsystem_kernel.dylib          0x0000000197cac4fc 0x197c90000 + 115964
1   libdispatch.dylib               0x0000000197b70a04 0x197b5c000 + 84484
2   libdispatch.dylib               0x0000000197b5f874 0x197b5c000 + 14452

Thread 2:
0   libsystem_kernel.dylib          0x0000000197cabb6c 0x197c90000 + 113516
1   libsystem_pthread.dylib         0x0000000197d71530 0x197d70000 + 5424
2   libsystem_pthread.dylib         0x0000000197d71020 0x197d70000 + 4128

Thread 3:
0   libsystem_kernel.dylib          0x0000000197cabb6c 0x197c90000 + 113516
1   libsystem_pthread.dylib         0x0000000197d71530 0x197d70000 + 5424
2   libsystem_pthread.dylib         0x0000000197d71020 0x197d70000 + 4128

Thread 4:
0   libsystem_kernel.dylib          0x0000000197cabb6c 0x197c90000 + 113516
1   libsystem_pthread.dylib         0x0000000197d71530 0x197d70000 + 5424
2   libsystem_pthread.dylib         0x0000000197d71020 0x197d70000 + 4128

Thread 5:
0   libsystem_kernel.dylib          0x0000000197cabb6c 0x197c90000 + 113516
1   libsystem_pthread.dylib         0x0000000197d71530 0x197d70000 + 5424
2   libsystem_pthread.dylib         0x0000000197d71020 0x197d70000 + 4128

Thread 6:
0   libsystem_kernel.dylib          0x0000000197cabb6c 0x197c90000 + 113516
1   libsystem_pthread.dylib         0x0000000197d71530 0x197d70000 + 5424
2   libsystem_pthread.dylib         0x0000000197d71020 0x197d70000 + 4128

Thread 0 crashed with ARM Thread State (64-bit):
    x0: 0x0000000000000000   x1: 0x0000000000000000   x2: 0x0000000000000000   x3: 0x000000015de5fd77
    x4: 0x00000001969d2e02   x5: 0x000000016fd434f0   x6: 0x000000000000006e   x7: 0x0000000000000f80
    x8: 0x0000000008000000   x9: 0x0000000004000000  x10: 0x0000000000000002  x11: 0x0000000000000010
   x12: 0x0000000000000000  x13: 0x0000000000000002  x14: 0x0000000000000000  x15: 0x0000030000000300
   x16: 0x0000000000000148  x17: 0x0000000000000000  x18: 0x0000000000000000  x19: 0x0000000000000006
   x20: 0x000000019e56e000  x21: 0x000000016fd434f0  x22: 0x000000015dd1d850  x23: 0x000000019e579b68
   x24: 0x0000000000000001  x25: 0x8f00d94271ca61a3  x26: 0x000000015de06e90  x27: 0x0000000000000000
   x28: 0x0000000000000001  fp: 0x000000016fd43450   lr: 0x0000000197d74ef8
    sp: 0x000000016fd43430   pc: 0x0000000197cab140 cpsr: 0x00000000

Binary Images:
0x1000bc000 - 0x1001c7fff xxxxxx arm64  <226243ce7a863e8bb7caa28732081d55> /var/mobile/Containers/Bundle/Application/9F859536-E359-41FC-B3CA-398683B8E19F/xxxxxx.app/xxxxxx
0x120074000 - 0x12009ffff dyld arm64  <d4078742b8573661b9fe465518caed3c> /usr/lib/dyld
0x180984000 - 0x180afdfff AVFoundation arm64  <62f9cc16934936bdbae949eff468326a> /System/Library/Frameworks/AVFoundation.framework/AVFoundation
0x180b00000 - 0x180b78fff libAVFAudio.dylib arm64  <85d9da197673373dad866aa3adafb789> /System/Library/Frameworks/AVFoundation.framework/libAVFAudio.dylib
0x180bc8000 - 0x180bc8fff Accelerate arm64  <52640254a7693f1a8c93b76f152d9a01> /System/Library/Frameworks/Accelerate.framework/Accelerate
0x180be0000 - 0x180e3cfff vImage arm64  <a03cc73bb24b378dbe34367137d0dede> /System/Library/Frameworks/Accelerate.framework/Frameworks/vImage.framework/vImage
0x180e40000 - 0x180eebfff libBLAS.dylib arm64  <60ad0764403e345d8052faa2af69b0e2> /System/Library/Frameworks/Accelerate.framework/Frameworks/vecLib.framework/libBLAS.dylib
0x180eec000 - 0x181251fff libLAPACK.dylib arm64  <e580decf91913736ae6eeb322862a7ce> /System/Library/Frameworks/Accelerate.framework/Frameworks/vecLib.framework/libLAPACK.dylib
0x181254000 - 0x181268fff libLinearAlgebra.dylib arm64  <9b0f1a9d4b0732a99de47e6a432afbf8> /System/Library/Frameworks/Accelerate.framework/Frameworks/vecLib.framework/libLinearAlgebra.dylib
0x18126c000 - 0x18127bfff libSparseBLAS.dylib arm64  <4a63abb231bb311d81eaa09cc4f1bde2> /System/Library/Frameworks/Accelerate.framework/Frameworks/vecLib.framework/libSparseBLAS.dylib
0x18127c000 - 0x1812e8fff libvDSP.dylib arm64  <0ce42521abc03db78fa29dfc23b655c4> /System/Library/Frameworks/Accelerate.framework/Frameworks/vecLib.framework/libvDSP.dylib
0x1812ec000 - 0x18130efff libvMisc.dylib arm64  <71a81d7189ca3ee8b646cb3fef50a781> /System/Library/Frameworks/Accelerate.framework/Frameworks/vecLib.framework/libvMisc.dylib
0x181310000 - 0x181310fff vecLib arm64  <d70ec799b3ed3850a50a89ef334c6f73> /System/Library/Frameworks/Accelerate.framework/Frameworks/vecLib.framework/vecLib
0x181314000 - 0x18134bfff Accounts arm64  <d450c8357bed3844af4977c553405f72> /System/Library/Frameworks/Accounts.framework/Accounts
0x181350000 - 0x1813cbfff AddressBook arm64  <50989572ec193435a3be9a5b5d4b049a> /System/Library/Frameworks/AddressBook.framework/AddressBook
0x1813cc000 - 0x1814a1fff AddressBookUI arm64  <d4f59dc6959e31a1be6ee551a1bd4349> /System/Library/Frameworks/AddressBookUI.framework/AddressBookUI
0x1814a4000 - 0x1814b7fff AssetsLibrary arm64  <248d6b2b00b635bc891dd23b5e9fd582> /System/Library/Frameworks/AssetsLibrary.framework/AssetsLibrary
0x181680000 - 0x1819a6fff AudioToolbox arm64  <c5d82c44162134029e93db6b2d932258> /System/Library/Frameworks/AudioToolbox.framework/AudioToolbox
0x181bc8000 - 0x181e55fff CFNetwork arm64  <8dfb8c9f8cf432929e7bdc050b518fac> /System/Library/Frameworks/CFNetwork.framework/CFNetwork
0x181e58000 - 0x181f07fff CloudKit arm64  <58c8abfb8f42382f83b0f473a508fad0> /System/Library/Frameworks/CloudKit.framework/CloudKit
0x181f08000 - 0x181f8ffff Contacts arm64  <11560b1bad78334daacc38851f7e5182> /System/Library/Frameworks/Contacts.framework/Contacts
0x181f90000 - 0x18208efff ContactsUI arm64  <1050eff6141b3013b44bc9c823872b1d> /System/Library/Frameworks/ContactsUI.framework/ContactsUI
0x182090000 - 0x18214bfff CoreAudio arm64  <3e2a210c14fe3aea910a71d076244cb3> /System/Library/Frameworks/CoreAudio.framework/CoreAudio
0x182164000 - 0x182185fff CoreBluetooth arm64  <a1b17bfbccd23ca989973171b638b575> /System/Library/Frameworks/CoreBluetooth.framework/CoreBluetooth
0x182188000 - 0x1823d1fff CoreData arm64  <8c6127652dce3ab8adf9e0ce964c67d2> /System/Library/Frameworks/CoreData.framework/CoreData
0x1823d4000 - 0x18274bfff CoreFoundation arm64  <ff1340241cb339f88865829dd82f7638> /System/Library/Frameworks/CoreFoundation.framework/CoreFoundation
0x18274c000 - 0x1828b9fff CoreGraphics arm64  <be820db45b2b3c1587783e96e4976102> /System/Library/Frameworks/CoreGraphics.framework/CoreGraphics
0x1828c4000 - 0x1828c6fff libCGXType.A.dylib arm64  <5ef23d77e9e138cb94ab74822bb3f654> /System/Library/Frameworks/CoreGraphics.framework/Resources/libCGXType.A.dylib
0x182abc000 - 0x182adafff libRIP.A.dylib arm64  

I am not sure what is the cause. Could someone point me on right direction?

Let me know if you need any code. Right now I am not posting anything, as I don't the cause of crash as its working fine on my device.

Answer 1

The problem was at below line

NSMutableAttributedString *nsmStr = 
     [[NSMutableAttributedString alloc] 
     initWithString:@""];
                     ^^ I can't define blank for NSMutableAttributedString
                     from iOS 9 onwards