DigiCDC not working with attiny85

[wujiang]

Code I was testing is:

#include <DigiCDC.h>
void setup() {                
  // initialize the digital pin as an output.
  SerialUSB.begin(); 
}

void loop() {
  SerialUSB.println(F("TEST!")); 
}

First, I got an error saying *** [.pio/build/digispark-tiny/lib1e8/DigisparkCDC/usbdrvasm.asm.o] Error 1. After removing ~/.platformio/packages/framework-arduino-avr-digistump/libraries/DigisparkCDC/usbdrvasm.asm the error was gone.

But nothing came out of serial monitor. Does anyone know how to fix it?