xcode 4.2 doesn't show errors at build

xcode 4.2 build 4D177b doesn't show error in the issue navigator. When I build the app it pop开发者_开发知识库s up the build failed, but in the issue navigator the reason doesn't appear. I'm attaching a screenshot about the problem. How can I see the errors?

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i've had issues where the workspace is invalid or corrupt due to pods needing update. if you've switched to a different source control branch recently and pods have changed, and your pods configuration expects a pod that hasn't been installed yet, sometimes it won't display the errors for your main target. try pod install to make sure the workspace, which is managed by cocoapods, is current.