1.2 Included Header File

The xc.h header file allows code in the source file to access compiler-specific or device-specific features. Based on your selected device, the compiler sets macros that allow avr/io.h to vector to the correct device-specific header file. Do not include a device-specific header in your code or your code will not be portable.

This and other header files can be found in the MPLAB XC8 installation directory in the avr/avr/include/avr or dfp/xc8/avr/include/avr subdirectories, or from paths specified via the -mdfp option.