When i enable all exceptions breakpoint my app always stops in AppDelegate, but im able to continue the program execution, but its very annoying cause always takes me to the appdelegate. Any ideas why?
Only enable Objective-C breakpoints.
To see the actual statement that is causing the error add an exception breakpoint:
From the Main Menu Debug:Breakpoints:Create Exception Breakpoint.
Right-click the breakpoint and set the exception to Objective-C. This will ignore other types of exceptions such as from C++. There are parts of the APIs that use exceptions such as Core Data (Apple is Special).
Add an action: "po $arg1".
Run the app to get the breakpoint and you will be at the line that causes the exception and the error message will be in the debugger console.
Breakpoint example:
If you're using Swift, or you want to have all the exceptions captured, you can change an option on All Exceptions to automatically continue after evaluating actions. Just find it in the Breakpoint Navigator and right/ctrl click the all Exceptions Breakpoint to edit it:
Then check the Options box:
Exceptions in C++ code common and normal. The exception breakpoint catches every raised exception even when they are being handled correctly. So if you don't specify Obj-C only you will notice that execution stops in a lot of seemingly random places. I run into this all the time with AVAudioPlayer especially.
Another thing to look out for are missing assets. I came across this question from another asker who seems to have also run into the same issue.
Xcode throws an exception in Main() in iOS 8 with 'all exceptions' breakpoint
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I'm new with Ios programming Objective-C language and my app was working great until suddenly stop working and get this error
Xcode show me a generic error and i want to know which function or instruction produce this error i couldn't find how to do this with Xcode i want just to point the problem where it may come from
This is the error i got :
Add Exception breakpoint
As shown in the image, select the 8th tab(Exception) and from the below add button, add the Exception Breakpoint. This will show the exact line of code from where the application crashes.
Add Exception breakpoint
How to create exception breakpoints in Xcode?
Exception breakpoints are a powerful debugging tool that remarkably
few people know about, so please read the following carefully and put
it into practice!
A regular breakpoint is on a line you specify and causes the debugger
to pause execution at that point so you can evaluate your program's
state. An exception breakpoint tells the debugger to pause whenever a
problem is encountered anywhere in your program, so you can evaluate
your program's state before it crashes.
Exception breakpoints are trivial to set up: go to the Breakpoint
Navigation (Cmd+8), then click the + button in the bottom left and
choose Add Exception Breakpoint. You can leave it there if you want
to, but it's preferable to make one further change to reduce
unnecessary messages: right-click on your new breakpoint, choose Edit
Breakpoint, then change the Exception value from "All" to
"Objective-C".
Please follow the below steps.
Run your project.
I've set an "All Exceptions" exception breakpoint for my project. In Xcode 7, it mysteriously fires on launch in main.m, but there doesn't seem to be anything obviously wrong. On continuing, the app runs normally.
Even running the project in Xcode 6 now causes this breakpoint to fire.
I can't figure out what is causing this. The threads don't indicate anything specific to what the cause is.
Maybe it's some sort of font issue in the Storyboard or something? Does anyone know a fix?
NOTE: It's a C++ exception, not Objective-C. Perhaps due to missing fonts. Xcode throws an exception in Main() in iOS 8 with 'all exceptions' breakpoint
I have almost the identical problem in Xcode 7, as of beta 3. This workaround solved it for me.
Because it's a C++ exception, you can change your "All Exceptions" breakpoint to catch only Objective-C exceptions. Having done this, I no longer hit the mystery break on startup, and because I'm not writing C++, get 99% of the value of having the "All Exceptions" break point on.
Here's how:
Go to the breakpoints tab (View > Navigators > Show Breakpoint Navigator or ⌘7).
Right click on the All Exceptions breakpoint and "Edit Breakpoint..."
Change the Exceptions covered to Objective-C only.
I started seeing the same behaviour in my application using the shorthand dictionary initialisation #{ ...: ... } in the willFinishLaunchingWithOptions function.
The problem was solved by replacing it with dictionaryWithObjectsAndKeys instead. I'm not sure if this was specific to my case or if the compiler has some kind of a problem with the shorthand syntax, but it's worth checking out if you're using that syntax.
Is it possible to turn off debug mode for a specific .m file ?
Summary.
I am writting a framework which will be used in other projects, code contains #try #catch blocks, which handles some exceptions.
Problem.
If framework user turns on Xcode's "All exceptions" breakpoints, then LLDB periodically stops program (when exception is raised) in #try block.
What I want.
I want to mark my framework files "non sensitive" for lldb (ignore exception breakpoints).
Solutions that I have already tried.
I tryed python script which checks eax/r0 and ignores exception, also a variant with breakpoint condition, but all this solutions are not nice for thousand of newbie third party developers.
Is it possible to have some nice solution?
Thanks.
This previous answer demonstrates how you can create a conditional exception breakpoint for your project. It may be a lot of work to specifically exclude each one of your framework's classes.
Hello I am making a cocos2d side scroller. I am trying to add a background audio file. I am using SimpleAudioEngine. This is the code:
[[SimpleAudioEngine sharedEngine]playBackgroundMusic:#"Soundtrack.mp3" loop:YES];
But when I run it it gives me a error. The line that it says is giving me the error is:
[audioSourcePlayer prepareToPlay];
Is there a different way to add a sound file that won't give me this error?
The AVAudio and OpenAL will throw some exceptions, it's normal that the Xcode exception breakpoint triggers and nothing to worry about.
Instead of removing the exception breakpoint I highly recommend to "edit" the breakpoint and from the tiny edit dialog make sure you select that only Objective-C exceptions are caught. That way all the audio exceptions won't bother you (they're C++ exceptions) but you can still see where things crash should an assertion trigger.
When I crash (for reasons I understand; that's not the problem) when I try to do something Cocoa isn't okay with, such as calling a method that doesn't exist or attempting to insert nil into a set, the debugger shows the stack from main() to __pthread_kill, without any of the frames that were present when the actual crashing code ran. There is a frame (9th from main) called objc_exception_rethrow. This leads me to believe that Cocoa Touch is trying to do something or other to recover all exceptions and die gracefully or something. However, it is very irritating when debugging to not have the ability to actually use Xcode4's debugging tools to investigate the calling stack frames, or even see where in my code I crashed.
Is there some way to make the objc_exception_rethrow behavior not happen, and just crash as soon as an exception is raised? Perhaps there's a debug setting that makes it crash earlier (at the right time)? (I haven't messed with any of the build settings in this project yet.)
I don't know any Xcode setting that could disable re-throwing exceptions. To my knowledge they are re-thrown by the runtime. You could try running the app without the debugger attached and let it crash. The crash report should contain a section "Last Exception Backtrace" which will give you exactly what you need in this case.
I found the answer: set a breakpoint on Obj-C Exceptions. It will go to the debugger when objc_exception_throw is hit, which is good. Unfortunately, this happens before the exception is printed, but we can make that happen anyway (most of the time) by setting the breakpoint's action to be (Debugger Action) po *(id *)($ebp + 8).