iOS: Debugging not working in XCode

Question

I'm using XCode 4 and iOS SDK 4.3. My debugging worked fine but now i discovered that when setting a breakpoint, the app pauses but XCode doesn't focus on the line in the Editor. Also the green arrow is not displayed when hitting the break point. I have a UINavigationController which is allocated in the AppDelegate. When i set a breakpoint in the didFinishLaunchingWithOptions everything works as expected:

This is when i a breakpoint has paused the app in the mapViewController which is the first item added to the navigation controller. (No green arrow but app is paused):

I really have no clue why debugging is working in AppDelegate but not in this controller. If you need additional info or screenshots in order to help me, please tell me.

UPDATE:

Now it's even not working in AppDelegate and changed nothing. I can also step through the lines and can see that values are assigned in the Locals and can therefore guess where the app is currently in the code. So obviously everything works, just the currently executed line is not marked as it should.

Answer 1

In xCode4:

• Your Project Name -> Edit Scheme
• Info tab (in run configuration)
• Set Build Configuration to "Debug", Debugger - to "LLDB" ("GDB" was before)
• Run your project

Worked for me. For "LLDB" green line is visible. Switching back to "GDB" brings me to this issue again.