There is only one file type that uses the .XCCONFIG extension:
Xcode Configuration Settings File
Configuration file created by Xcode, a Mac OS X software development application; stores parameters for configuring the build of Xcode projects; can be referenced by multiple Xcode projects to use the same build settings.
To create the XCCONFIG file, open the project you want to create the XCCONFIG file for, select, choose "Other" (under iOS and OS X), select "Configuration Settings File," name the file, choose the save location, and click .
Updated: March 8, 2014