My team uses Kotlin-Native to develop our iOS APP.
When a crash happend in kotlin, the crash call stack is not complete. But when I debug the app in XCode, the crash call stack is complete.
When I disconnect XCode and trigger the same crash in the app, and then connect to XCode the view crash log (XCode > Window > Devide and Simulator > view device logs), I find that one stack frame disappears, the red line in the image below:
My team found out the 'objc2kotlin' function has a bug: The assembly code of objc2kotlin doesn't change the value of fp(frame pointer, x29) after pushing lr(link register, x30) and fp(frame pointer, x29).
Hope Kotlin-Native team fix the bug quickly, thank you very much.
Related
this is a simple game running on iphone device, it will crash in some cases.but xcode only display this message:
error: memory read failed for 0xd00000000
there is no stack in the left panel.
i found the value in register pc 0xd00000000, it looks like the base address of this process.
i have add a exception breakpoint in xcode it will not active before crash.
this is the memory usage image, i have test it on iphone x:
so i want to know, how to find the directy reason of this crash? is there any method to break the process when the register change to a special value, in this case, when the pc register change to 0xd00000000, make xcode break.
stackoverflow exception cause this crash, it make my stack memory crashed,so xcode can't get the valid stacktrace of this tread.
After working just fine on both iPhone and iPad for a month, my Xcode 9 app has consistently started crashing causing me the following fatal problem: When I build & run it on an iPhone (simulator or device) Xcode completes loading the app and then crashes too fast for me to copy/paste the error from the debugger. When I run on iPad it works fine leading me to believe this is a result of something related to the split master/detail view.
If I use either an exception breakpoint or an "all C++ exceptions" it will stop at the AppDelegate class and crash if I hit play. If I use only an "all Objective-C exceptions" it will crash as before.
In the debug view hierarchy I get the following errors as well:
Error: Unable to capture view hierarchy.
Details: Log Title: Data source expression execution failure.
Log Details: error evaluating expression “(id)
[[(Class)objc_getClass("DBGTargetHub") sharedHub]
performRequestWithRequestInBase64:#"...
Log Method: -[DBGDataSourceConnectionLibViewDebugger
_executeLLDBExpression:forRequest:onPotentialThread:iteration:]
_block_invoke_2
Method: -[DBGViewDebugger updateDebugHierarchy]_block_invoke_2
I have tested other apps and this issue is unique to the app I am working on. Any ideas or debugging tips for how to proceed? I might just have to redo this whole project again if I can't even find the root cause of this! Appreciate any help.
Quick solution: Reset Simulator Device
I managed to resolve the above issue thanks to some serious digging. First, to resolve the instantaneous crash problem, I set a breakpoint at every line in the app delegate. That allowed me to narrow the error to a memory handling problem. From there I started running the code on one of each device available, and realized the crash only occurred on devices I had used earlier in development. Resetting those devices solved the problem.
The core issue here is that when you clean/rebuild your xcode program, it updates the app code on the device, but not necessarily the data model information. So when I changed my data model by including new data and renaming old data it was not properly updated.
When I try to build and run my keyboard extension, it sometimes just crashes with a Thread 1: signal SIGQUIT.
I am not able to reproduce the error. Sometimes I can build and run my app but most of the time the keyboard just quits. This happens on an actual device. In the simulator it does not open my keyboard and says Waiting to Attach.
The console does not output any errors at first. However, if I change the dropdown to View UI Hierachy in the Debug navigator I get the following description:
Details: No plist data for fetching view hierarchy: error evaluating expression “(id)[(Class)objc_getClass("DBGViewDebuggerSupport_iOS") fetchViewHierarchyWithOptions:(id)[(Class)objc_getClass("NSDictionary") dictionaryWithObjects:(id)[(id)[(id)[(Class)objc_getClass("NSArray") arrayWithObject:(id)[(Class)objc_getClass("NSNumber") numberWithBool:1]] arrayByAddingObject:(id)[(id)[(Class)objc_getClass("NSArray") arrayWithObject:#"_UIVisualEffectBackdropView"] arrayByAddingObject:#"_UIBackdropEffectView"]] arrayByAddingObject:(id)[(Class)objc_getClass("NSNumber") numberWithBool:0]] forKeys:(id)[(id)[(id)[(Class)objc_getClass("NSArray") arrayWithObject:#"DBGViewDebuggerUseLayersAsSnapshots"] arrayByAddingObject:#"DBGViewDebuggerEffectViewsToSnapshotAsImage"] arrayByAddingObject:#"DBGViewDebuggerAlwaysEncodeLayers"]]]”: error: Execution was interrupted, reason: EXC_BREAKPOINT (code=1, subcode=0x18daddc34).
The process has been returned to the state before expression evaluation.
Method: -[DBGAbstractViewDescriber handleFetchedViewInfo:fetchError:resultHandler:]
Please file a bug at http://bugreport.apple.com with this warning message and any useful information you can provide.
I also took a screenshot of the processes.
Am I doing something wrong and how could I prevent that my keyboard extension quits all the time when running it? Is it actually a bug as it says in the description?
DISCLAIMER
It seems like something in xCode 8.2.1 is broken and the debugger is not correctly attaching to the correct process or the hosting process is not properly loading the new code.
This is a not a permanent solution but a temporary workaround.
WORKAROUND
I have been able to work around this issue by following the steps below.
Kill any process that is using your keyboard (important!)
Launch the application using the debugger so the latest code is deployed to the device
Navigate to Settings > General > Keyboards > etc.
Remove your custom keyboard
Re-add your custom keyboard
Debug the application once again
The reason this works is because removing the keyboard kills the process that is hosting the extension allowing Xcode to attach to the new binary.
As I understand this is a bug in Xcode 8.2.1. because before update my custom keyboard was working very well.
this is a temporary solution.
Run your code like always!
Bring up your keyboard until the error (SIGQUIT) appear!
Goto xcode > debug > detach
Goto again Xcode > debug > Attach to Process: attach the keyboard (it should be first process)
now, your breakpoints will work. but there are no log output unfortunately! I hope it temporary solve your problem
Fun error that ONLY happens in iOS 10, when debugging on a physical device. It does not happen in the simulator, or when running on the physical device (while not debugging). It also does not happen on an iOS 9 device in any situation...only iOS 10 while debugging and after any javascript call has been executed.
I have a hybrid web app, written in Swift 2.3, after the xwebview loads I call various javascript methods...actually, any in this case. Anyway, after the javascript method has finished I get a malloc error saying I'm trying to free a pointer.
malloc: *** error for object 0x1740b5060: pointer being freed was not allocated
*** set a breakpoint in malloc_error_break to debug
So I set the break point...and it never breaks on the breakpoint, it just keeps telling me to set a breakpoint.
If I remove all of my javascript calls, the error never happens. I've tried enabling them one by one, it doesn't matter, they all break after the callback returns.
I've been after this for about 2 weeks, I'm out of extra hair to pull out. At this point I'd love to hear if someone else is seeing the same thing.
It looks like its a safari bug and therefore only appears when you are debugging your webview with safari. In Safari under Develop->Your_Device_Name uncheck "Automatically Show Web Inspector for JSContexts".
This should resolve your issue.
I'm getting a really weird EXC_BAD_ACCESS(Code=EXC_ARM_DA_ALIGN) crash on my app which is written in swift but only when i run it on a 32 bit device and only if its running from Xcode (the device is still hooked to Xcode), If i start the app without Xcode it runs fine. I can't give any code since no matter what i do i get no stack trace or anything like that .Only the mention error on the AppDelegate, even though the crash is in different screens further in the app (crashes on second screen).
Any idea as to why the crash would happen only when Xcode is running the app
You are using some variable or object which is yet to be initialised. Please review your code and you will get the error. You can add exceptional break point to get the actual position of the error.
It's a memory alignment issue. Search on EXC_ARM_DA_ALIGN.
https://brewx.qualcomm.com/bws/content/gi/common/appseng/en/knowledgebase/docs/kb95.html
use memcpy
char*Code; int pc;
double f;
memcpy(Code+pc, &f, sizeof(f)); // instead of *(double*)(Code+pc)=f; that generates EXC_ARM_DA_ALIGN