title: ios app crashes with no error and no crash report
body: <p>I am currently importing all the facebook birthdays and inserting them in core data,then i sort them according to the latest bday's(fetching and sorting).
  When i use facebook to sync and get all the contacts,my app retrieves all the contacts perfectly,but after it receives the contacts it soon crashes..</p>
  
  <p>i tried using zombie objects.</p>
  
  <p>i tried leaks. </p>
  
  <p>i tried adding an exception in exception navigator.</p>
  
  <p>i synced my ipod with itunes went to library and device logs but couldnt find any file which says low memory issue or something that sorta.</p>
  
  <p>i am confused because the reason for the crash doesnt show up,it simply crashes and when i open my app again i can see all the contacts imported from facebook</p>
  
  <p>there is no lldb in the debugger window,when i change it to gdb,i can see gdb but when i use backtrace(bt) it say "No Stack"</p>
  
  <p>i also noticed there is one thing i.e if there are too many contacts my app crashes and if there are less contacts it works normally.</p>
  
  <p>what can be the problem? does it crash because of a memory issue?
  how am i supposed to know what is causing the crash?</p>
  
  <p>thanks</p>