Xcode: Internal error occurred while creating dependency graph

I just started getting this error today, seeming开发者_开发知识库ly out of nowhere. Any one see this before and know what causes it.

Internal error occurred while creating dependency graph: *** -[NSCFArray initWithObjects:count:]: attempt to insert nil object at objects[10]

This happens when I try to build with "iPhone Device 3.x" selected. However, if I select "iPhone Simulator 3.x", everything is fine.

I am using Xcode 3.2.1.

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I found the solution to my problem and it was quite simple.

1. Quit Xcode
2. Reopen Xcode
3. Open your project
4. Clean All Targets

Now everything works fine although I wish I knew how I got into that state.

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You have an NSArray or NSMutableArray into which you are trying to insert a nil or uninitialized object. As the documentation for these two arrays indicates, this is not allowed.

You need to troubleshoot where you are inserting values into an array (presumably objects) and find out where that nil value is coming from.