Identifying Crash in Symbolized Crash Report - ios

Question

I've had a crash within my native iOS App (which runs fine on simulator, only error on a device) I've been unable to identify the issue. The crash happens while the splash screen is shown, before the initial view controller is shown. Here are the 3 steps I've done thus far:
1) turned on all exception breakpoints. By doing so, the exception shows up in main.m. Here is the code:
// main.m
#import <UIKit/UIKit.h>
#import "idcAppDelegate.h"
int main(int argc, char * argv[])
{
#autoreleasepool {
return UIApplicationMain(argc, argv, nil, NSStringFromClass([idcAppDelegate class]));
}
}
2) looked at the crash log and symboized it. Here is the output. The only view controller shown in line 5 of crash report (below) is EngineeringViewController.m with line #741 of my code. I checked that code and included that in #3 below. Also, as a test I put a breakpoint prior to that line of code being called, and it never reached that code. Any insight to the issues would be appreciated.
Incident Identifier: 1C053572-AFE5-4EB6-A95C-9E4459B860A7
CrashReporter Key: f97ebe907a31ab39c017e93a637e9e195e90d8f4
Hardware Model: iPhone5,1
Process: idcdoor [267]
Path: /private/var/mobile/Containers/Bundle/Application/8ED83A36-2A92-4601-9265- 392A9E97E89B/idcdoor.app/idcdoor
Identifier: com.zen.idcdoor
Version: 1.0 (1.0)
Code Type: ARM (Native)
Parent Process: launchd [1]
Date/Time: 2014-11-01 10:26:23.652 -0500
Launch Time: 2014-11-01 10:26:20.975 -0500
OS Version: iOS 8.1 (12B411)
Report Version: 105
Exception Type: EXC_BAD_ACCESS (SIGSEGV)
Exception Subtype: KERN_INVALID_ADDRESS at 0x00000014
Triggered by Thread: 0
Thread 0 name: Dispatch queue: com.apple.main-thread
Thread 0 Crashed:
0 libsystem_c.dylib 0x354877d4 strlen + 28
1 CoreFoundation 0x2771440c __CFStringAppendFormatCore + 7052
2 CoreFoundation 0x2771285c _CFStringCreateWithFormatAndArgumentsAux2 + 76
3 Foundation 0x2837f86e -[NSPlaceholderString initWithFormat:locale:arguments:] + 134
4 Foundation 0x2837f770 +[NSString stringWithFormat:] + 56
5 idcdoor 0x000a8e48 -[EngineeringViewController pickerView:numberOfRowsInComponent:] (EngineeringViewController.m:741)
6 UIKit 0x2accc60a -[UISectionRowData refreshWithSection:tableView:tableViewRowData:] + 2546
7 UIKit 0x2accbb54 -[UITableViewRowData rectForFooterInSection:heightCanBeGuessed:] + 324
8 UIKit 0x2accb994 -[UITableViewRowData heightForTable] + 52
9 UIKit 0x2accb7cc -[UITableView _updateContentSize] + 340
10 UIKit 0x2acd151e -[UITableView didMoveToWindow] + 66
11 UIKit 0x2abfbe50 -[UIView(Internal) _didMoveFromWindow:toWindow:] + 1308
12 UIKit 0x2ac1ac96 -[UIScrollView _didMoveFromWindow:toWindow:] + 46
13 UIKit 0x2abfbbc0 -[UIView(Internal) _didMoveFromWindow:toWindow:] + 652
14 UIKit 0x2abfbbc0 -[UIView(Internal) _didMoveFromWindow:toWindow:] + 652
15 UIKit 0x2abfb4d4 __45-[UIView(Hierarchy) _postMovedFromSuperview:]_block_invoke + 108
16 UIKit 0x2abfb3e8 -[UIView(Hierarchy) _postMovedFromSuperview:] + 424
17 UIKit 0x2ac0584a -[UIView(Internal) _addSubview:positioned:relativeTo:] + 1458
18 UIKit 0x2ac0528e -[UIView(Hierarchy) addSubview:] + 26
19 UIKit 0x2ae58cb4 -[UIPickerView layoutSubviews] + 3212
20 UIKit 0x2ae5a322 -[UIPickerView selectedRowInComponent:] + 42
21 UIKit 0x2ae56bfc -[UIPickerView _updateSelectedRows] + 124
22 UIKit 0x2ae56d0a -[UIPickerView didMoveToWindow] + 94
23 UIKit 0x2abfbe50 -[UIView(Internal) _didMoveFromWindow:toWindow:] + 1308
24 UIKit 0x2abfbbc0 -[UIView(Internal) _didMoveFromWindow:toWindow:] + 652
25 UIKit 0x2abfbbc0 -[UIView(Internal) _didMoveFromWindow:toWindow:] + 652
26 UIKit 0x2abfbbc0 -[UIView(Internal) _didMoveFromWindow:toWindow:] + 652
27 UIKit 0x2abfb4d4 __45-[UIView(Hierarchy) _postMovedFromSuperview:]_block_invoke + 108
28 UIKit 0x2abfb3e8 -[UIView(Hierarchy) _postMovedFromSuperview:] + 424
29 UIKit 0x2ac0584a -[UIView(Internal) _addSubview:positioned:relativeTo:] + 1458
30 UIKit 0x2ac0528e -[UIView(Hierarchy) addSubview:] + 26
31 UIKit 0x2acb142a -[UINavigationTransitionView transition:fromView:toView:] + 474
32 UIKit 0x2acb1246 -[UINavigationTransitionView transition:toView:] + 22
33 UIKit 0x2aca8af2 -[UINavigationController _startTransition:fromViewController:toViewController:] + 2282
34 UIKit 0x2aca7f7e -[UINavigationController _startDeferredTransitionIfNeeded:] + 574
35 UIKit 0x2aca7ce8 -[UINavigationController __viewWillLayoutSubviews] + 40
36 UIKit 0x2aca7c7c -[UILayoutContainerView layoutSubviews] + 180
37 UIKit 0x2abfc4d2 -[UIView(CALayerDelegate) layoutSublayersOfLayer:] + 510
38 QuartzCore 0x2a624a08 -[CALayer layoutSublayers] + 132
39 QuartzCore 0x2a6203e0 CA::Layer::layout_if_needed(CA::Transaction*) + 356
40 QuartzCore 0x2a620268 CA::Layer::layout_and_display_if_needed(CA::Transaction*) + 12
41 QuartzCore 0x2a61fc4c CA::Context::commit_transaction(CA::Transaction*) + 220
42 QuartzCore 0x2a61fa50 CA::Transaction::commit() + 320
43 UIKit 0x2ae601c0 -[UIApplication _reportMainSceneUpdateFinished:] + 40
44 UIKit 0x2ae60f68 -[UIApplication _runWithMainScene:transitionContext:completion:] + 2508
45 UIKit 0x2ae6b374 __84-[UIApplication _handleApplicationActivationWithScene:transitionContext:completion:]_block_invoke + 32
46 UIKit 0x2ae5f384 -[UIApplication workspaceDidEndTransaction:] + 128
47 FrontBoardServices 0x2decc0e6 __31-[FBSSerialQueue performAsync:]_block_invoke + 10
48 CoreFoundation 0x2770639a __CFRUNLOOP_IS_CALLING_OUT_TO_A_BLOCK__ + 10
49 CoreFoundation 0x2770565c __CFRunLoopDoBlocks + 212
50 CoreFoundation 0x27704196 __CFRunLoopRun + 1710
51 CoreFoundation 0x2765220c CFRunLoopRunSpecific + 472
52 CoreFoundation 0x2765201e CFRunLoopRunInMode + 102
53 UIKit 0x2ac633ea -[UIApplication _run] + 554
54 UIKit 0x2ac5e1cc UIApplicationMain + 1436
55 idcdoor 0x000af77e main (main.m:17)
56 libdyld.dylib 0x3546aaac start + 0
Thread 1 name: Dispatch queue: com.apple.libdispatch-manager
Thread 1:
0 libsystem_kernel.dylib 0x3551d2a0 kevent64 + 24
1 libdispatch.dylib 0x354569fc _dispatch_mgr_invoke + 276
2 libdispatch.dylib 0x3544c20e _dispatch_mgr_thread + 34
Thread 2:
0 libsystem_kernel.dylib 0x355319cc __workq_kernreturn + 8
1 libsystem_pthread.dylib 0x355abea8 _pthread_wqthread + 788
2 libsystem_pthread.dylib 0x355abb80 start_wqthread + 4
Thread 3:
0 libsystem_kernel.dylib 0x355319cc __workq_kernreturn + 8
1 libsystem_pthread.dylib 0x355abea8 _pthread_wqthread + 788
2 libsystem_pthread.dylib 0x355abb80 start_wqthread + 4
Thread 4:
0 libsystem_kernel.dylib 0x355319cc __workq_kernreturn + 8
1 libsystem_pthread.dylib 0x355abea8 _pthread_wqthread + 788
2 libsystem_pthread.dylib 0x355abb80 start_wqthread + 4
Thread 0 crashed with ARM Thread State (32-bit):
r0: 0x00000014 r1: 0x00000014 r2: 0x00000000 r3: 0x01010101
r4: 0x00000000 r5: 0x277ab8d9 r6: 0x001ca2f8 r7: 0x001ca2f0
r8: 0x001ca884 r9: 0x00000001 r10: 0x001ca434 r11: 0x277ab8d9
ip: 0x00000018 sp: 0x001ca2f0 lr: 0x27714411 pc: 0x354877d4
cpsr: 0x60000010
Binary Images:
0x9e000 - 0xbdfff idcdoor armv7 <3a3e81a535e33b749617ea74b35051a4> /var/mobile/Containers/Bundle/Application/8ED83A36-2A92-4601-9265-392A9E97E89B/idcdoor.app/idcdoor
0x264f000 - 0x265afff GAXClient armv7s <2a03ff3e6ca83b138ffe5e1436d3a686> /System/Library/AccessibilityBundles/GAXClient.bundle/GAXClient
0x1fee5000 - 0x1ff08fff dyld armv7s <b01d37db5b0d3a2ea1ccf17afc40a896> /usr/lib/dyld
0x25d80000 - 0x25d88fff AccessibilitySettingsLoader armv7s <46e9b9bae13d3590971aca226c70bb90> /System/Library/AccessibilityBundles/AccessibilitySettingsLoader.bundle/AccessibilitySettingsLoader
0x25f48000 - 0x25f63fff libJapaneseConverter.dylib armv7s <708b951369ca3c6ca3c04cff645cb4af> /System/Library/CoreServices/Encodings/libJapaneseConverter.dylib
0x25f64000 - 0x25f85fff libKoreanConverter.dylib armv7s <12d4496cb7e234ef9248a8133281466f> /System/Library/CoreServices/Encodings/libKoreanConverter.dylib
0x25f8d000 - 0x25f9bfff libSimplifiedChineseConverter.dylib armv7s <710dea62fe2532bd833dc37458e8df31> /System/Library/CoreServices/Encodings/libSimplifiedChineseConverter.dylib
0x25f9e000 - 0x25fb0fff libTraditionalChineseConverter.dylib armv7s <b671c9d6a27e3125ab87d2b889e52885> /System/Library/CoreServices/Encodings/libTraditionalChineseConverter.dylib
0x261d6000 - 0x26342fff AVFoundation armv7s <20cb3fb302c83ede8cc708d8dea2b480> /System/Library/Frameworks/AVFoundation.framework/AVFoundation
0x26343000 - 0x263a1fff libAVFAudio.dylib armv7s <07753e16a2e136e2bbe7937c1d2833f6> /System/Library/Frameworks/AVFoundation.framework/libAVFAudio.dylib
0x263db000 - 0x263dbfff Accelerate armv7s <3c10ee15d8363fa58b719f2abca91b06> /System/Library/Frameworks/Accelerate.framework/Accelerate
0x263ec000 - 0x26607fff vImage armv7s <3358de09601333a2881365e5c74c681e> /System/Library/Frameworks/Accelerate.framework/Frameworks/vImage.framework/vImage
0x26608000 - 0x266eefff libBLAS.dylib armv7s <b46b7fd3985f371ca26b10f268965e63> /System/Library/Frameworks/Accelerate.framework/Frameworks/vecLib.framework/libBLAS.dylib
0x266ef000 - 0x269b3fff libLAPACK.dylib armv7s <eb228c255d9e349391cd6b227a9d2744> /System/Library/Frameworks/Accelerate.framework/Frameworks/vecLib.framework/libLAPACK.dylib
0x269b4000 - 0x269c5fff libLinearAlgebra.dylib armv7s <d2e989bc1bad320b918c37d3642db4b6> /System/Library/Frameworks/Accelerate.framework/Frameworks/vecLib.framework/libLinearAlgebra.dylib
0x269c6000 - 0x26a42fff libvDSP.dylib armv7s <07cf0625bd813336920eb5b62f99be06> /System/Library/Frameworks/Accelerate.framework/Frameworks/vecLib.framework/libvDSP.dylib
0x26a43000 - 0x26a55fff libvMisc.dylib armv7s <07997e6e46fa35a18c6ddacf62f326d8> /System/Library/Frameworks/Accelerate.framework/Frameworks/vecLib.framework/libvMisc.dylib
0x26a56000 - 0x26a56fff vecLib armv7s <108b763f155130828fa123813e3ff5f5> /System/Library/Frameworks/Accelerate.framework/Frameworks/vecLib.framework/vecLib
0x26a57000 - 0x26a7dfff Accounts armv7s <7540bbbab44638cbbfc6f8e660b882e5> /System/Library/Frameworks/Accounts.framework/Accounts
0x26a7f000 - 0x26aeffff AddressBook armv7s <f14b87a5995235f7b4758b9177eacfff> /System/Library/Frameworks/AddressBook.framework/AddressBook
0x26af0000 - 0x26c14fff AddressBookUI armv7s <4cbc3a35503334398504bec12f184406> /System/Library/Frameworks/AddressBookUI.framework/AddressBookUI
0x26dad000 - 0x27020fff AudioToolbox armv7s <6af7bb73fc8a3820aaeddf4be11d76d1> /System/Library/Frameworks/AudioToolbox.framework/AudioToolbox
0x2718b000 - 0x27313fff CFNetwork armv7s <447c648544f63bad945945978a4420cc> /System/Library/Frameworks/CFNetwork.framework/CFNetwork
0x27314000 - 0x27395fff CloudKit armv7s <a36362766d2d34a89f0375dc3af0b266> /System/Library/Frameworks/CloudKit.framework/CloudKit
0x27396000 - 0x273f5fff CoreAudio armv7s <fc17e188a69f32b8b7a5eb739e71628a> /System/Library/Frameworks/CoreAudio.framework/CoreAudio
0x27410000 - 0x2742dfff CoreBluetooth armv7s <7013619ef098351e9327893736f9ac75> /System/Library/Frameworks/CoreBluetooth.framework/CoreBluetooth
0x2742e000 - 0x27639fff CoreData armv7s <c9df4ab3eb933030a3cec50334b917ce> /System/Library/Frameworks/CoreData.framework/CoreData
0x2763a000 - 0x27966fff CoreFoundation armv7s <88f8b217c0ee3ea99fc535279a274e51> /System/Library/Frameworks/CoreFoundation.framework/CoreFoundation
0x27967000 - 0x27a91fff CoreGraphics armv7s <89608951c9173d66ba6318cfe83636cd> /System/Library/Frameworks/CoreGraphics.framework/CoreGraphics
0x27ad1000 - 0x27ad3fff libCGXType.A.dylib armv7s <e655cd9db7ee35779038050110716bdf> /System/Library/Frameworks/CoreGraphics.framework/Resources/libCGXType.A.dylib
0x27ad4000 - 0x27adefff libCMSBuiltin.A.dylib armv7s <edc7a2d9b3ec34599184c14a1558e306> /System/Library/Frameworks/CoreGraphics.framework/Resources/libCMSBuiltin.A.dylib
0x27cc6000 - 0x27ce1fff libRIP.A.dylib armv7s <7245d28cd0683999ba311e1f9c44eaf0> /System/Library/Frameworks/CoreGraphics.framework/Resources/libRIP.A.dylib
0x27ce2000 - 0x27df0fff CoreImage armv7s <5c9817ffa8c939878f34e92794fe01d0> /System/Library/Frameworks/CoreImage.framework/CoreImage
0x27df1000 - 0x27e48fff CoreLocation armv7s <a25b4e5cd9db3552b17f6f933c268b4e> /System/Library/Frameworks/CoreLocation.framework/CoreLocation
0x27e7a000 - 0x27f14fff CoreMedia armv7s <c0207b0eb8a6372c82765e3f9aaae9c2> /System/Library/Frameworks/CoreMedia.framework/CoreMedia
0x27f15000 - 0x27fd4fff CoreMotion armv7s <eaf2bec24a9a339b8a72e66a50f84195> /System/Library/Frameworks/CoreMotion.framework/CoreMotion
0x27fd5000 - 0x28033fff CoreTelephony armv7s <d387fea5262f3a1a9b915eda86a9c521> /System/Library/Frameworks/CoreTelephony.framework/CoreTelephony
0x28034000 - 0x280fbfff CoreText armv7s <27a6c9f02e0c3fcdb25aa629dbac8420> /System/Library/Frameworks/CoreText.framework/CoreText
0x280fc000 - 0x28111fff CoreVideo armv7s <710cbdb8798d3e7e862a5c77ebb278b4> /System/Library/Frameworks/CoreVideo.framework/CoreVideo
0x28112000 - 0x28207fff EventKit armv7s <f5e8d9857bca3d30a82884f74acccdd9> /System/Library/Frameworks/EventKit.framework/EventKit
0x2837e000 - 0x28580fff Foundation armv7s <dae281def68e3062826ad439cc878f35> /System/Library/Frameworks/Foundation.framework/Foundation
0x285ad000 - 0x285ccfff GSS armv7s <3d6d5fcf16673331b532dc80bc9cb004> /System/Library/Frameworks/GSS.framework/GSS
0x28660000 - 0x286b6fff IOKit armv7s <694427785d6b3b158555dbb2de06ba5d> /System/Library/Frameworks/IOKit.framework/Versions/A/IOKit
0x286b7000 - 0x288f9fff ImageIO armv7s <7805efbe771f3abe8eb78f8a11e43510> /System/Library/Frameworks/ImageIO.framework/ImageIO
0x288fa000 - 0x28c48fff JavaScriptCore armv7s <8efe7fde7fc334d3b4e7154fd1ad7934> /System/Library/Frameworks/JavaScriptCore.framework/JavaScriptCore
0x28f25000 - 0x28f2dfff MediaAccessibility armv7s <39f640b059a43b609c3f03d2c53ccca3> /System/Library/Frameworks/MediaAccessibility.framework/MediaAccessibility
0x28f2e000 - 0x29107fff MediaPlayer armv7s <c97f5d8967cd331687edef49d2e330ea> /System/Library/Frameworks/MediaPlayer.framework/MediaPlayer
0x29108000 - 0x29481fff MediaToolbox armv7s <61a8287d7db23902ace54438be5d01dd> /System/Library/Frameworks/MediaToolbox.framework/MediaToolbox
0x29482000 - 0x29540fff MessageUI armv7s <4d650e3067b53974b00534275f6f4e90> /System/Library/Frameworks/MessageUI.framework/MessageUI
0x29541000 - 0x295adfff Metal armv7s <55c278f571e43337a9f50f33fd7a0e19> /System/Library/Frameworks/Metal.framework/Metal
0x295ae000 - 0x2963efff MobileCoreServices armv7s <d309a94eb41f3828888fea191d26c2b4> /System/Library/Frameworks/MobileCoreServices.framework/MobileCoreServices
0x2a11a000 - 0x2a122fff OpenGLES armv7s <da72e0ef6bad373e9f10a34e7e8e69c4> /System/Library/Frameworks/OpenGLES.framework/OpenGLES
0x2a124000 - 0x2a124fff libCVMSPluginSupport.dylib armv7s <19d9172837f5361d938ae1757caf9c37> /System/Library/Frameworks/OpenGLES.framework/libCVMSPluginSupport.dylib
0x2a125000 - 0x2a127fff libCoreFSCache.dylib armv7s <ecc01c4cd2aa3cfabe2cb655e944d675> /System/Library/Frameworks/OpenGLES.framework/libCoreFSCache.dylib
0x2a128000 - 0x2a12bfff libCoreVMClient.dylib armv7s <f9bbda54797d3b119f02b904b5b616b8> /System/Library/Frameworks/OpenGLES.framework/libCoreVMClient.dylib
0x2a12c000 - 0x2a134fff libGFXShared.dylib armv7s <a4f8148c427c3a1da2d6e4f7d8f44db0> /System/Library/Frameworks/OpenGLES.framework/libGFXShared.dylib
0x2a135000 - 0x2a177fff libGLImage.dylib armv7s <25bf18582842387aadbef55023603f1b> /System/Library/Frameworks/OpenGLES.framework/libGLImage.dylib
0x2a618000 - 0x2a76afff QuartzCore armv7s <f279312e24013b3facfd0701a8f856f2> /System/Library/Frameworks/QuartzCore.framework/QuartzCore
0x2a76b000 - 0x2a7befff QuickLook armv7s <4faa07b11c763d2e8535a9eeae067d73> /System/Library/Frameworks/QuickLook.framework/QuickLook
0x2a9ad000 - 0x2a9edfff Security armv7s <de3cef25d1443557af5def374133b390> /System/Library/Frameworks/Security.framework/Security
0x2ab91000 - 0x2abedfff SystemConfiguration armv7s <f0007f16cef530dcb1681ab29db8e311> /System/Library/Frameworks/SystemConfiguration.framework/SystemConfiguration
0x2abf0000 - 0x2b491fff UIKit armv7s <30f3605a26bc3155a5dbffdf1f30d2ab> /System/Library/Frameworks/UIKit.framework/UIKit
0x2b492000 - 0x2b4f9fff VideoToolbox armv7s <2a114ceb99013b3bb24c7d5544f0a575> /System/Library/Frameworks/VideoToolbox.framework/VideoToolbox
0x2b4fa000 - 0x2b6dffff WebKit armv7s <adbe79a7e1fe3e4a96388bbead166d3f> /System/Library/Frameworks/WebKit.framework/WebKit
0x2ba00000 - 0x2ba0bfff AOSNotification armv7s <9692b7bd225438e7b7832f56454a2857> /System/Library/PrivateFrameworks/AOSNotification.framework/AOSNotification
0x2bacf000 - 0x2bad6fff AccessibilityUI armv7s <5b632cc5cff034f9a3e1e533421dc2f1> /System/Library/PrivateFrameworks/Accessibility.framework/Frameworks/AccessibilityUI.framework/AccessibilityUI
0x2baee000 - 0x2baf1fff AccessibilityUIUtilities armv7s <e7c5cd1c1c223fad9e1b1d9471c1044a> /System/Library/PrivateFrameworks/Accessibility.framework/Frameworks/AccessibilityUIUtilities.framework/AccessibilityUIUtilities
0x2baf4000 - 0x2baf7fff ZoomServices armv7s <734b9fb4cf9b30f79573a25e471d55dd> /System/Library/PrivateFrameworks/Accessibility.framework/Frameworks/ZoomServices.framework/ZoomServices
....
3) here is code from EngineeringViewController.m
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component {
if([pickerView isEqual: _pickerPreferredId]){
return sizeof(Preffered_ID);
}else if([pickerView isEqual: _pickerDrum]){
int drumCount = 0;
if(doorLiftSelection == 0){
for (int i = 0; i < sizeof Select_Drum[10]; i++){
//line 741
if([[NSString stringWithFormat: #"%s",Select_Drum[i][10]] isEqualToString:#"Standard"]){
drumCount++;
}
}
}

Answer 1

At the time of the crash, Select_Drum[i][10] is not a valid C string.
CF is trying to create a CFString/NSString from it and is crashing when trying to strlen() on the string to determine how much memory it needs to allocate for the resulting CFString.
As for why it's not a valid C string, you'll need to look at it with the debugger, but this line looks VERY suspect:
for (int i = 0; i < sizeof Select_Drum[10]; i++)
I don't think that does what you think it does.