CMake Error at TRANSFORM-selector-AT-wrong-argument.cmake:[0-9]+ \(file\):
  Error evaluating generator expression:

    \$<LIST:TRANSFORM,a;b,TOUPPER,AT,0,1x,2>

  sub-command TRANSFORM, selector AT: '1x': unexpected argument.
Call Stack \(most recent call first\):
  CMakeLists.txt:[0-9]+ \(include\)