Cocoapods: Unknown object version

[cheng77]

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What did you do?

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What did you expect to happen?

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What happened instead?

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e.g. Pod A is missing the subspec B for target C.

CocoaPods Environment

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Project that demonstrates the issue

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[dnkoutso]

please fill in the issue template.

From the title though you should upgrade xcodeproj gem to 1.5.9. gem update xcodeproj