title: Debug objc_msgSend crash I cant reproduce
body: <p>I've had some crash reports from bugsense for my iOS app I'm not able to reproduce and so not to debug. It happens more than 200 times a day so I guess it's quite serious.</p>
  
  <p>I've read something about NSZombie but I'm not able to reproduce the crash so I guess it's useless.
  Here is a crash report:</p>
  
  <pre><code>SIGSEGV
  0 libobjc.A.dylib 0x3aa515b0 objc_msgSend + 15
  1 UIKit 0x34d493df + 294
  2 UIKit 0x34cae469 + 52
  3 QuartzCore 0x34926099 + 160
  4 QuartzCore 0x34925ff1 + 64
  5 IOMobileFramebuffer 0x36ba1fd7 + 154
  6 IOKit 0x33920449 IODispatchCalloutFromCFMessage + 192
  7 CoreFoundation 0x32d035db + 118
  8 CoreFoundation 0x32d0e173 + 34
  9 CoreFoundation 0x32d0e117 + 138
  10 CoreFoundation 0x32d0cf99 + 1384
  11 CoreFoundation 0x32c7febd CFRunLoopRunSpecific + 356
  12 CoreFoundation 0x32c7fd49 CFRunLoopRunInMode + 104
  13 GraphicsServices 0x368562eb GSEventRunModal + 74
  14 UIKit 0x34b95301 UIApplicationMain + 1120
  15 My Bet main (main.m:16) Live 0x000705e7 0x6d000 + 13799
  </code></pre>
  
  <p>On some similar threads they believe the problem can be in UIAlertView, so here is an example on how I use them:
  in file.h</p>
  
  <pre><code>UIAlertView *alertView;
  </code></pre>
  
  <p>in file.m</p>
  
  <pre><code>-(void)wait{
  UIActivityIndicatorView * activityView = [[UIActivityIndicatorView alloc]initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge];
  activityView.frame = CGRectMake(121.0f, 50.0f, 37.0f, 37.0f);
  [activityView startAnimating];
  alertView = [[UIAlertView alloc] initWithTitle:NSLocalizedString(@"Searching...", @"") message:nil delegate:nil cancelButtonTitle:nil otherButtonTitles:nil];
  [alertView addSubview:activityView];
  [alertView show];
  [NSThread detachNewThreadSelector:@selector(function) toTarget:self withObject:nil];
  }
  -(void)function{
  // Do some web request
  [alertView dismissWithClickedButtonIndex:0 animated:NO];
  if(response == nil){
      UIAlertView *alert = [[UIAlertView alloc] initWithTitle:NSLocalizedString(@"Timeout", @"") message:NSLocalizedString(@"Connection timeout", @"") delegate:nil cancelButtonTitle:NSLocalizedString(@"Close", @"") otherButtonTitles:nil ];
      [alert show];
  }
  }
  </code></pre>
  
  <p>Any hint on how I can procede to solve this?
  Thanks</p>