I synced to the latest 3.1 branch and get the following error on my trinket
Two other changes is that I installed 1.5.8 and added the tiny directory to /hardware as they suggest.
In file included from /Users/zekekoch/Google Drive/Arduino/libraries/FastLED/clockless.h:22,
from /Users/zekekoch/Google Drive/Arduino/libraries/FastLED/FastLED.h:33,
/Users/zekekoch/Google Drive/Arduino/libraries/FastLED/clockless_trinket.h: In static member function ‘static void ClocklessController<DATA_PIN, T1, T2, T3, RGB_ORDER, XTRA0, FLIP, WAIT_TIME>::showRGBInternal(PixelController<RGB_ORDER>&)’:
/Users/zekekoch/Google Drive/Arduino/libraries/FastLED/clockless_trinket.h:249: error: ‘TIFR0’ was not declared in this scope