Arduino:1.6.4 (Windows 7), 板:"Arduino Mega or Mega 2560, ATmega2560 (Mega 2560)"
c:/program files/arduino/hardware/tools/avr/bin/../lib/gcc/avr/4.8.1/../../../../avr/lib/avr6/crtm2560.o.init9+0x0): undefined reference to `main'
collect2.exe: error: ld returned 1 exit status