Xcode debugger problem

I'm trying to debug my code with the help of the de开发者_开发知识库bugger in Xcode, but when I'm trying to step in, nothing is happening. I tried it with another project and it's debugging fine there.

What could be the cause of this problem?

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Some times xCode takes much time to calculate data, so its just shows stepping over. In this situation you can NSLog your values to debug.