title: EXC_BAD_ACCESS on iOS in system libraries
body: <p>I'm having an EXC_BAD_ACCESS exception in an iOS game made in Xcode. It happens on the Simulator and on real devices. It's always at the same part in the game, but does not always happen. It's cryptic because it does not seem to have anything to do with the game's objects, just with default library/system methods. Xcode also does not show which line of code is causing it (but it shows which line in <em>assembly</em>). I'm posting the backtrace below. What could be causing it? How can I find out what is the problem?</p>
  
  <pre><code>thread #1: tid = 0x1c03, 0x01980051 libobjc.A.dylib`_cache_getImp + 9, stop reason = EXC_BAD_ACCESS (code=1, address=0xc0000008)
  frame #0: 0x01980051 libobjc.A.dylib`_cache_getImp + 9
  frame #1: 0x0196dac4 libobjc.A.dylib`lookUpMethod + 42
  frame #2: 0x0196da88 libobjc.A.dylib`class_respondsToSelector + 65
  frame #3: 0x023160d3 CoreFoundation`objectIsKindOfClass + 51
  frame #4: 0x0239f087 CoreFoundation`__handleUncaughtException + 71
  frame #5: 0x0196f0b9 libobjc.A.dylib`_objc_terminate() + 86
  frame #6: 0x01da2a65 libc++abi.dylib`safe_handler_caller(void (*)()) + 13
  frame #7: 0x01da2acd libc++abi.dylib`std::terminate() + 23
  frame #8: 0x01da3c4e libc++abi.dylib`__cxa_rethrow + 83
  frame #9: 0x0196efbd libobjc.A.dylib`objc_exception_rethrow + 47
  frame #10: 0x022bbf98 CoreFoundation`CFRunLoopRunSpecific + 360
  frame #11: 0x022bbe1b CoreFoundation`CFRunLoopRunInMode + 123
  frame #12: 0x01df57e3 GraphicsServices`GSEventRunModal + 88
  frame #13: 0x01df5668 GraphicsServices`GSEventRun + 104
  frame #14: 0x00aa5ffc UIKit`UIApplicationMain + 1211
  frame #15: 0x000026e1 Game`main(argc=1, argv=0xbffff3bc) + 95 at main.m:6
  frame #16: 0x00002645 Game`start + 53
  </code></pre>