I have tried building the very simple blink example from the FastLED library for Teensy LC but I cannot get it to build. I have tried it with the following:

Teensyduino 1.47 Arduino 1.8.9
Teensyduino 1.48 Arduino 1.8.10

I have also tried using VisualTeensy and both of the above with no joy. It fails on multiple files with the following warnings, here is an example but it is repeated many times:

LIB [CPP] wiring.cpp
In file included from lib/FastLED//platforms/arm/kl26/clockless_arm_kl26.h:4:0,
from lib/FastLED//platforms/arm/kl26/fastled_arm_kl26.h:7,
from lib/FastLED//platforms.h:20,
from lib/FastLED//FastLED.h:52,
from lib/FastLED//wiring.cpp:2:
lib/FastLED//platforms/arm/kl26/../common/m0clockless.h: In function 'int showLedData(volatile uint32_t*, uint32_t, const uint8_t*, uint32_t, M0ClocklessData*)':
lib/FastLED//platforms/arm/kl26/../common/m0clockless.h:316:40: error: 'SysTick' was not declared in this scope
uint32_t ticksBeforeInterrupts = SysTick->VAL;
lib/FastLED//platforms/arm/kl26/../common/m0clockless.h:326:36: error: 'VARIANT_MCK' was not declared in this scope
const uint32_t kTicksPerMs = VARIANT_MCK / 1000;
Any ideas?