CMake Error at NonValidTarget-TARGET_PROPERTY.cmake:1 \(add_custom_command\):
  Error evaluating generator expression:

    \$<TARGET_PROPERTY:NotAProperty>

  \$<TARGET_PROPERTY:prop> may only be used with binary targets.  It may not
  be used with add_custom_command or add_custom_target.  Specify the target
  to read a property from using the \$<TARGET_PROPERTY:tgt,prop> signature
  instead.
Call Stack \(most recent call first\):
  CMakeLists.txt:3 \(include\)