I have these lines in .gitignore file:

• Carthage/Checkouts
• Carthage/Build

Can I then use carthage update --use-submodules? Because when I tried to use this command, directory Carthage/Checkouts is staged in git repository even though is declared in .gitignore file.

When I unstage content of this repository and run carthage update --use-submodules again, this error is throwed:

*** Fetching Alamofire
*** Fetching VaultKit
Parse error: expected submodule commit SHA in ls-tree output: 

Another question: If I want to use submodules, must I use flag --use-submodules with every carthage update command? Or should I use it only with first carthage update?