Macports with Xcode CLI tools only

I ve installed the latest version of MacPorts and Xcode CLI tools for OS X 10.10 - I don't want download 4GB of data because I need only GCC. Everything looks fine - I can download and compile ports, except the one thing - every time when I try to install new port I get following messages:

Warning: xcodebuild exists but failed to execute
Warning: Xcode does not appear to be installed; most ports will likely fail to build.

But as I said before everything works fine. Should I worry or just ignore these messages?