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Here’s a brief list of possible bugs:

*Forgetting to removeObserver from the NSNotificationCenter and then releasing that object that needs removed first. The only hint that you get from PB’s debugger is the line “_CFNotificationCenterPostLocalNotification” on a SIG abort.

I think this would be better off filed on SignalsSentOnCrash, assuming you do mean this error message occurs on SIGABRT. If no objections come along, I or someone else will/should move it.

That isn’t a bad idea, but SignalsSentOnCrash is a clean list that only describes what the signals are and a very general description of the cause. I have also noticed that this particular bug source can cause a SIGBUS or a SIGABRT. I just thought that it might be nice to share possible bug sources that are hard to catch but easy to create. I also thought that it might be nice to point out the smoking gun in the debugging output that points toward the culprit. Maybe I could create a new page named PossibleSIGABRTCauses. Any votes?

No, put it with SignalsSentOnCrash for now. There’s not enough information to warrant a whole new page yet. Best keep it where people can find it - and looking up “SIGABRT” would lead one to SignalsSentOnCrash. We can always factor back out into a new page later, and create a decent organizational system then.

Awhile back, BruceB added that using the wrong specifier for an integer variable (probably not just integers) in NSLog would generate a Signal 10 SIGBUS error:

NSLog( @”%@”, i ); // Signal 10 SIGBUS error

NSLog( @”%d”, i ); // correct

Doing tre above is the same thing as sending a message to a deallocated instance of a class, and not relly a case of “wrong specifer”. When NSLog sees %@, it expects the variable to be a pointer to a calls, which it can send a -description message to. So in this case, it interprets i as a pointer address, and sending a message to an arbitrary memory location, is always a crash. –EnglaBenny

The original error stemmed from some overzealous copy and pasting. The correction is obvious once identified, but buried in the middle of a number of NSLog statements, it was difficult to see. Using %@ as a descriptor will be new for many of us coming from the C/C++ world.

Does anyone have a list of the SIGXXX error numbers? look in /usr/include/sys/signal.h