Using Xcode on Mac (with MacPort as example) may end up with the following error :
Warning: The Command Line Tools for Xcode don’t appear to be installed; most ports will likely fail to build.
Once Xcode has been installed, you need to manually install the Command Line Tool from the Xcode Download Component preference panel.
– Open Xcode
– Click on Xcode menu and then Preferences
– Locate the Download icon and then the Components tab
– Click on Command Line Tools and then the Install button.
The Command Line Tools component is about 180 Mb. Once downloaded and installed, the error should be gone.