title: App crashes on device with latest Facebook iOS SDK
body: <p>My app compiles and runs correctly in Simulator but not when I run it on my device.  I'm using the latest Facebook SDK build.  I'm using XCode 3.2.6, LLVM compiler 1.7 and testing on my device iPhone 4 running iOS 4.3.5.  I get the following error:</p>
  
  <pre><code>Program received signal:  “SIGSYS”.
  warning: Unable to read symbols for /Developer/Platforms/iPhoneOS.platform/DeviceSupport/4.3.5 (8L1)/Symbols/Developer/usr/lib/libXcodeDebuggerSupport.dylib (file not found).
  Xcode could not locate source file: FBSettings.m (line: 65)
  (gdb) bt
  #0  0x00080324 in __33+[FBSettings autoPublishInstall:]_block_invoke_0 (.block_descriptor=0x4e) at /Users/jacl/src/ship/ios-sdk/src/FBSettings.m:65
  #1  0x336226aa in dispatch_once$VARIANT$up ()
  #2  0x0008031c in +[FBSettings autoPublishInstall:] (self=0x4e, _cmd=0x2fdfdc48, appID=&lt;value temporarily unavailable, due to optimizations&gt;) at once.h:68
  #3  0x00077d48 in -[FBSession initWithAppID:permissions:urlSchemeSuffix:tokenCacheStrategy:] (self=&lt;value temporarily unavailable, due to optimizations&gt;, _cmd=0x2fdfdc48, appID=&lt;value temporarily unavailable, due to optimizations&gt;, permissions=&lt;value temporarily unavailable, due to optimizations&gt;, urlSchemeSuffix=&lt;value temporarily unavailable, due to optimizations&gt;, tokenCachingStrategy=&lt;value temporarily unavailable, due to optimizations&gt;) at /Users/jacl/src/ship/ios-sdk/src/FBSession.m:244
  #4  0x00077950 in -[FBSession init] (self=&lt;value temporarily unavailable, due to optimizations&gt;, _cmd=&lt;value temporarily unavailable, due to optimizations&gt;) at /Users/jacl/src/ship/ios-sdk/src/FBSession.m:153
  #5  0x0007877e in +[FBSession activeSession] (self=&lt;value temporarily unavailable, due to optimizations&gt;, _cmd=&lt;value temporarily unavailable, due to optimizations&gt;) at /Users/jacl/src/ship/ios-sdk/src/FBSession.m:446
  #6  0x0002d704 in -[FacebookClient initWithContext:andDocumentsPath:] (self=0x2ae5a0, _cmd=0x9259c, context=0x2bb1b0, path=0x28b0b0) at /Users/username/projects/myapp/myapp-ios/Classes/FacebookClient.m:84
  #7  0x00003586 in -[MyAppDelegate application:didFinishLaunchingWithOptions:] (self=0x28be00, _cmd=0x3587dbfe, application=0x263f40, launchOptions=0x0) at /Users/username/projects/myapp/myapp-ios/Classes/MyAppDelegate.m:234
  #8  0x355c1820 in -[UIApplication _callInitializationDelegatesForURL:payload:suspended:] ()
  #9  0x355bbb64 in -[UIApplication _runWithURL:payload:launchOrientation:statusBarStyle:statusBarHidden:] ()
  #10 0x355907d6 in -[UIApplication handleEvent:withNewEvent:] ()
  #11 0x35590214 in -[UIApplication sendEvent:] ()
  #12 0x3558fc52 in _UIApplicationHandleEvent ()
  #13 0x35ecae76 in PurpleEventCallback ()
  #14 0x3677da96 in __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ ()
  #15 0x3677f83e in __CFRunLoopDoSource1 ()
  #16 0x3678060c in __CFRunLoopRun ()
  #17 0x36710ec2 in CFRunLoopRunSpecific ()
  #18 0x36710dca in CFRunLoopRunInMode ()
  #19 0x355bad48 in -[UIApplication _run] ()
  #20 0x355b8806 in UIApplicationMain ()
  #21 0x00002858 in main (argc=1, argv=0x2fdff488) at /Users/username/projects/myapp/myapp-ios/main.m:14
  </code></pre>
  
  <p>The code referenced (FBSettings.m line 65) doesn't seem particularly problematic:</p>
  
  <pre><code>+ (void)autoPublishInstall:(NSString *)appID {
      if ([FBSettings shouldAutoPublishInstall]) {
          dispatch_once(&amp;g_publishInstallOnceToken, ^{
              // dispatch_once is great, but not re-entrant.  Inside publishInstall we use FBRequest, which will
              // cause this function to get invoked a second time.  By scheduling the work, we can sidestep the problem.
              [[FBSettings class] performSelector:@selector(publishInstall:) withObject:appID afterDelay:FBPublishDelay];
          });
      }
  }
  </code></pre>