CMake Error at bad-arguments\.cmake:[0-9]+ \(file\):
  Error evaluating generator expression:

    \$<FILE_SET_EXISTS:fs,opt,foo>

  \$<FILE_SET_EXISTS> expression requires 2 comma separated parameters, but
  got 3 instead.
Call Stack \(most recent call first\):
  CMakeLists\.txt:[0-9]+ \(include\)
