CMake Error at TARGET_NAME_IF_EXISTS-empty-arg.cmake:2 \(file\):
  Error evaluating generator expression:

    \$<TARGET_NAME_IF_EXISTS:>

  \$<TARGET_NAME_IF_EXISTS:tgt> expression requires a non-empty valid target
  name.
Call Stack \(most recent call first\):
  CMakeLists.txt:[0-9]+ \(include\)