WinAVR

To use EEPROM memory mapping on XMEGA, the address of EEPROM variables must
start at offset 0x1000 instead of 0. This should be done by changing all
the XMEGA linker scripts so the .eeprom section starts at 0x811000 instead
of 0x810000. There appear to be 35 linker script files that are affected.

AVR Studio debugger will currently not recognize EEPROM data at this
alternate starting address. I am submitting a request to Atmel to change
that. In the meantime, there is an easy work-around using avr-objcopy to
reset the EEPROM address so the debugger will recognize it:
avr-objcopy --change-section-vma .eeprom=0x810000 <target>.elf