Compile error if #define DEBUG_USB_HOST

Hi,
I am trying to debug samd usb host related function on nano 33 IOT.
I have added below 2 lines on USBHost/MouseController example.

#define SERIAL_PORT_MONITOR Serial1
#define DEBUG_USB_HOST

However, I see compile error below.
Does anyone know how to enable DEBUG_USB_HOST ?

sketch\MouseController.ino.cpp.o: In function HIDBoot<(unsigned char)2>::Init(unsigned long, unsigned long, unsigned long)': C:\Users\toshi\AppData\Local\Arduino15\packages\arduino\hardware\samd\1.8.6\libraries\USBHost\src/hidboot.h:481: undefined reference to NotifyFailGetDevDescr()’
C:\Users\toshi\AppData\Local\Arduino15\packages\arduino\hardware\samd\1.8.6\libraries\USBHost\src/hidboot.h:516: undefined reference to NotifyFail(unsigned char)' C:\Users\toshi\AppData\Local\Arduino15\packages\arduino\hardware\samd\1.8.6\libraries\USBHost\src/hidboot.h:499: undefined reference to NotifyFailSetConfDescr()’
collect2.exe: error: ld returned 1 exit status
exit status 1