_stack error

I’m trying to compile a modified version of Kevin’s serial_ports.zip but get the following error:

Error - could not find definition of symbol ‘_stack’ in file ‘C:\10byte frc_serial_ports\ifi_startup.o’.

The only extra files I’ve included are eeprom.c, eeprom.h and a custom header & source file.

This problem’s been bugging me for 2 hrs now. Any suggestions?

is _stack a variable your trying to use?