iOS-应用程序在预配置的iPad上崩溃，在模拟器中正常运行

Question

Here's the trace:

2012-10-17 14:46:42.280 Site Inspection Report[10446:907] *** Terminating app due to uncaught exception 'CALayerInvalidGeometry', reason: 'CALayer position contains NaN: [384 nan]'
*** First throw call stack:
(0x38af92a3 0x3141897f 0x38af91c5 0x3113c953 0x3113c87b 0x3113c80b 0x3597eaf5 0x354bf 0x33f97 0x3599c595 0x359dcd79 0x359d8aed 0x35a1a1d1 0x3331d 0x359ddad9 0x359dd663 0x359d584b 0x3597dc41 0x3597d6d5 0x3597d123 0x3497a5a3 0x3497a1d3 0x38ace173 0x38ace117 0x38accf99 0x38a3febd 0x38a3fd49 0x359d4485 0x359d1301 0x330f5 0x33090)
libc++abi.dylib: terminate called throwing an exception

Looking around SO the usually suspect in this is returning something being divided by 0 or some table related issue. I don't do any division in the app but I do have a table, so that's going to be my starting point. My question is, is there a way to decipher the message above that can provide a better starting point for debugging other than a 'blind squirrel' method?

Thanks

Answer 1

To get a better idea of the error and it's root cause add an exception breakpoint to get the line of code causing the error. Select the breakpoints and in the bottom left of the Xcode window select the "+" and click on "Add Exception Breakpoint". Click through the following alerts. This works best with Xcode 4.5.1.